The Proteas made it four wins on the spin in the shortest format – their best run since a five-match span between October 2018 and February 2019 – thanks to a dominant display at Stormont, despite making five changes to the team.
Bavuma struck his maiden T20I half-century, making 72 from 51 deliveries while opening the batting as South Africa posted an imposing total of 189-2.
Reeza Hendricks made 69 at the top of the order, helping put on 127 for the first wicket with his skipper. Ireland eventually broke the stand in the 16th over, though David Miller came out at three to produce a stunning late attack, blitzing 36 from just 17 deliveries.
The home team lost Kevin O'Brien to the ninth ball of their reply, setting the tone for wickets to fall at regular intervals. Andy Balbirnie top-scored with 27 before becoming one of three batsmen to be dismissed in the space of nine runs, ending any hope of an Irish victory as they slipped to 78-5.
George Linde, Lizaad Williams and Wiaan Mulder all claimed two wickets apiece but Ireland at least avoided being bowled out inside the distance, finishing up on 140-9.
Miller makes hay on tour
A late cameo in the third game completed an impressive series for Miller. The left-handed batsman finished up with 139 runs having been dismissed just once.
His strike-rate of 169.51 runs per 100 deliveries was the best for any South African who faced a minimum of 10 balls, aided by hitting 11 fours and six sixes.
Irish made to wait
Ireland's winless run in T20I action continues. It is now seven without success, with this result extending their longest drought in the format.
Even facing a much-changed line-up minus both Quinton de Kock and Tabraiz Shamsi, two pivotal players for the Proteas, they were well beaten having been far more competitive in the preceding 50-over fixtures between the nations.
The 29-year-old batsman suffered the injury when fielding in the high-scoring T20 defeat to England on Sunday and will sit out the upcoming Wanderers clash.
Cricket South Africa (CSA) said Bavuma could return for Sunday's second game in their three-match series against Australia and there would be no replacement called into the 16-player squad.
"The recommended recovery time for the injury is seven to 10 days," said CSA. "He will remain with the team and receive treatment from the medical staff."
Bavuma blasted a rapid 49 off just 24 balls at the top of the order in a five-wicket loss at SuperSport Park as England sealed a 2-1 series win.
Jos Buttler top scored with an unbeaten 94 from 82 balls, while Harry Brook (84) and Moeen Ali (51) struck quickfire half-centuries to get the tourists up to an imposing 342-7 at Mangaung Oval on Sunday.
That was not enough to set up a series decider, though, as captain Bavuma (109 off 102) crafted his first international century for a year as the Proteas pulled off the highest successful ODI run chase in Bloemfontein.
David Miller finished off the job with 58 not out from 37 balls as South Africa boosted their chances of securing direct qualification for the World Cup in India this year, consigning England to a fifth consecutive loss in this format.
Jason Roy fell for only nine after scoring a century in the first ODI on Friday and Dawid Malan (12) also failed, but Brook and Buttler put on 73 for the fourth wicket.
Brook raced to a half-century before falling to Aiden Markram and Moeen kept England ticking along nicely with his skipper until he played on to a delivery from Anrich Nortje (2-64).
Buttler and Sam Curran (28 off 17) cut loose as the world champions took 60 off the last four overs to seemingly take the upper hand.
Bavuma led by example to get his side off to a blistering start, combining with Quinton de Kock – who took a blow on the wrist while keeping but did not appear to be hampered – for 77.
Olly Stone (2-48) got rid of De Kock but Bavuma was in great touch with support from Rassie van der Dussen (38) as England – who left Jofra Archer out the paceman's long-awaited return in the opening match – were unable to halt the flow of runs.
Bavuma fell scooping Curran into his stumps soon after bringing up a sublime third ODI hundred to end a stand of 97 with Van der Dussen, who then became Adil Rashid's (2-72) second victim.
Heinrich Klaasen (27) failed to build on a start, but Miller and Marco Jansen (32no off 29) got South Africa home with five balls to spare – the left-hander fittingly winning it by clattering Chris Woakes for six.
Brook and Buttler pummel Proteas attack
Brook has made a great start to his international career and showed his class in only his second ODI after being dismissed for a duck on debut two days earlier.
He struck four sixes and seven fours before Buttler provided a late onslaught, getting his side up to a big total with support from Moeen and Curran.
The skipper cleared the rope on three occasions and struck eight boundaries, shifting through the gears in explosive fashion.
Brilliant Bavuma sets up record chase, Miller delivers again
Bavuma had not reached three figures for his country since his hundred against India last January, but he ended that wait in style.
With South Africa battling to seal their World Cup spot for the tournament in India, Bavuma batted beautifully to lay the platform at the top of the order.
Miller thrives on the responsibility of being the finisher and he delivered once again, hitting three sixes as South Africa bettered their previous best ODI run chase on this ground of 274-4 against Australia in 2020.
A match heavily impacted by rain concluded on Sunday, with South Africa declaring early on 173-5, but subsequently failing to bowl West Indies out in a little over two sessions.
The Windies reached 201-5 at stumps, chasing a target of 298, with Alick Athanaze (98) superbly marshalling the innings.
It left a Proteas bowling group that were already one player short - South Africa having gone with an extra batter for the first Test - frustrated.
"From our side, we tried our best to get a result in our favour," said Bavuma.
"But the wicket didn't break up as much as we expected. In the end, it was a good, competitive game of cricket.
"We went in with an extra batter as a cushion. As batters, we would like to be a bit more ruthless and convert those fifties into hundreds.
"We lost time because of the weather. With the bowling resources we had, we tried our best.
"A little bit more time and things could have been different."
Keshav Maharaj took 4-88 for South Africa, with Kagiso Rabada (1-38) the only other Proteas bowler to do any damage to the Windies during their second innings.
"I pride myself on playing Test cricket," said Maharaj. "I always relish a chance to bowl and the conditions suited me.
"I tried to keep repeating the process and keep things simple."
Windies captain Kraigg Brathwaite, meanwhile, was delighted with the grit his team displayed with the bat.
"Happy with our batting group," he said.
"The guys were quite positive, so [I'm] proud of the batting unit. We believed we could get those runs.
"It wasn't going to be easy. We need to keep going from strength to strength."
The second and final Test starts on Thursday.
A strong opening session for the visitors provided hope with the deficit just 138 at lunch, with South Africa already four wickets down at the Wanderers.
However, captain Bavuma turned the tide with a valiant display with the bat to put his side in cruise control and finished the day unbeaten on 171.
Just four runs shy of 3,000 in his Test career, Bavuma could start day four with two landmarks if he adds another 29 on Saturday.
Kyle Mayers struck twice early as West Indies took momentum, with Kemar Roach then landing the big wicket of Aiden Markram (18) as he forced an edge to Joshua Da Silva.
Bavuma led South Africa's recovery, putting on 37 with Ryan Rickelton (10) for the fourth wicket, but Raymon Reifer removed Rickelton in the last over before lunch to end the session on a high.
The Proteas responded in the second session, despite losing Heinrich Klaasen for 14, with Bavuma and Wiaan Mulder (42) adding a partnership of 103.
Mulder eventually fell to Alzarri Joseph after pulling a short ball to Tagenarine Chanderpaul, before Simon Harmer (19) was trapped lbw by Jason Holder.
South Africa will resume on 287-7 on day four assuming they do not declare overnight, with Bavuma presumably eager to complete his first ever Test double century.
Unstoppable Bavuma
When the South Africa captain walked out to bat, his side were 8-2 and had already lost Markram, but Bavuma repaired the innings and established a commanding lead with his second Test ton.
His tally leaves him sat on 2,996 runs in his Test career, with a landmark on the cards if South Africa do not declare overnight.
Mayers' strong start
Dismissing Dean Elgar (5) and Tony de Zorzi (1) inside the opening eight overs, Mayers looked to have put West Indies on course to clawing their way back into the Test.
He only conceded 25 runs from his 13 overs, but the tourists had no answer to Bavuma's stunning display.
Bavuma has not played for his country since suffering an elbow injury during a T20I series in India three months ago which ended 2-2.
The batter has since spoken of feeling "let down" after he was not selected for the inaugural SA20 auction this month.
Questions have been asked over Bavuma's credentials in the shortest format less than a month before the T20 World Cup in Australia begins.
The Proteas skipper is ignoring such "distractions" ahead of the opening T20I against the top-ranked side in the world at Greenfield Stadium in Thiruvananthapuram on Wednesday.
He said: "I've tried to put all those things behind me. My biggest focus is on the role that I have, which is to lead and serve the team as best as I can, make sure that the guys are in the best place possible going into that big World Cup tournament.
"All other distractions, all other sideshows, that's stuff that I'll deal with on a personal level, but now, here, being within the team, as long as I'm still wearing that shirt, it will be to lead and serve the team as best as I can."
Bavuma added: "This is our last series before the World Cup. Obviously we will be looking for this series to fill whatever gaps we feel there are in the team. We have guys who have been playing a lot of cricket and I guess we will be managing their intensity.
"We also have guys who need some cricket under their belts. It will be to give those guys some game time because this is our last preparation in different conditions compared to Australia but still match time nevertheless.
"The last time we were here, we were tested in all departments of our game and I think we answered well."
South Africa have beaten England and Ireland since drawing with India, who come into this series on the back of a 2-1 triumph over Australia.
The two sides will also meet in Group 2 at the World Cup in Perth on October 30.
Kohli to reach another landmark
Virat Kohli finally ended his long wait for an international hundred against Afghanistan in the Asia Cup this month.
The former skipper is set to bring up another century, as his next T20I innings will be his 100th. Kohli will be only the 10th player to be at the crease 100 times in the shortest format on the international stage.
Kohli has scored 3,660 runs from 99 innings, 684 more than the next best aggregate for any batter in their first 100 innings in men's T20Is (Martin Guptill – 2,976 runs).
Proteas enjoying life on the road
South Africa have won each of their past four completed T20I games away from home.
The Proteas have been victorious six times on tour in 2022. Only in 2021, when they won 14 times away from home, have they bettered that tally in a calendar year.
Needing to win both matches against the Dutch and hope Ireland lose at least one of their three matches against Bangladesh in May in order to qualify automatically for the World Cup, which will be held in India later this year, the Proteas eased to victory on Friday.
This ODI was the second of a three-match series that was supposed to take place in late 2021, but was postponed because of concerns over a COVID-19 variant. The first match ended with no result.
The importance of the match was reflected in the strong squad chosen by South Africa, with Anrich Nortje and Kagiso Rabada included despite their imminent IPL commitments.
Nortje played a key role in restricting the Netherlands to 189 all out despite scores of 45 and 48 from Vikramijit Singh and Teja Nidamanuru respectively, taking 2/24 off his eight overs while Sisanda Magala and Tabraiz Shamsi picked up three wickets each.
It was the Netherlands' second-highest ODI score against South Africa, but the Proteas cruised to the winning total regardless as Bavuma's sublime innings (90 not out from 79 balls) helped them to victory.
Aiden Markram chipped in with a half-century off just 37 balls, though it was his captain who finished the job as Bavuma smashed the ball back past bowler Ryan Klein for four to seal the win.
The three games in six days could have a major bearing on whether South Africa ease into the Cricket World Cup, or whether they have to go to the subsequent qualifying competition next year.
Series defeats to Sri Lanka and Pakistan, plus a draw with Ireland and an abandoned series against the Netherlands, have left the Proteas down in 10th position in the Cricket World Cup Super League after 10 games.
Bangladesh have played 15 games so far, winning 10 of those, and sit top of the table, just ahead of England, with India in third place.
South Africa have won all nine of their previous men's ODIs at home against Bangladesh, so they head into this series as firm favourites. A 3-0 ODI series win away to India in January showed their prowess, albeit that did not count towards World Cup qualification.
Bavuma said ahead of Friday's SuperSport Park opener: "We must make sure that we get ourselves in the right mental space. One of the things we have spoken about from a mental point of view is that coming up against a side like India generally it is easier for the guys to get themselves up.
"With Bangladesh, we can't afford to underestimate them in any way from a mental and intensity point of view and there can't be any sense of complacency."
Fitness concerns mean South Africa have not selected all-rounder Sisanda Magala. He is not injured and has performed strongly with the ball for the Lions in recent days, but South Africa do not see him being in the right physical shape to play international cricket.
Bavuma is a Lions club-mate of Magala but indicated the ruthless decision was one that he supported.
Speaking in a news conference on Friday, Bavuma said: "With Magala, he knows he can only point the finger back at himself and obviously as a captain I am disappointed that I don't have him at my disposal – but I think he can accept that it is his own doing."
The South Africa captain added, according to Times Live: "I play with the guy at the Lions, I have a good relationship with the fitness trainer and the communication that I have had is that there is a lot more good he is doing to try to improve his fitness. Unfortunately, at this time he is not at the eligible fitness level."
Bangladesh bidding to bounce back
Bangladesh suffered a seven-wicket loss to Afghanistan in their last ODI, bringing an end to a five-game winning streak in the format. It would be a statement result if they pulled off a win in any of their three games in South Africa, even though the Proteas have lost four of their last six completed men's ODIs in Centurion, including their last two. The Proteas have never lost more than two consecutive games in their 43 all-time fixtures at the venue.
Hosts go all out
A number of South Africa's big names will miss the Test series that follows the ODIs, as they head to the IPL, but the hosts will be fielding their strongest possible side in these limited-overs games. South Africa have scored an average of 300 runs per innings when batting first in men's ODIs since the beginning of 2021, the most of any team to have batted first more than once in that period and 53 runs more than Bangladesh (247).
Bavuma missed the Boxing Day Test through injury and was not selected for the next two despite the Proteas' obvious struggles in the batting department.
Having been told to return to domestic cricket and make his mark, the 29-year-old duly delivered with a superb 180 for the Lions against the Dolphins last week, his highest first-class score, and is likely to return to the South Africa XI in Johannesburg.
Beuran Hendricks, Keegan Petersen and Andile Phehlukwayo have also been included in the squad, with South Africa on the verge of going 2-1 down in the series with England poised to win the third Test in Port Elizabeth.
Hendricks and Phehlukwayo will fight it out to replace the suspended Kagiso Rabada.
South Africa squad to face England in the fourth Test: Faf du Plessis (capt), Quinton de Kock, Dean Elgar, Keshav Maharaj, Rassie van der Dussen, Pieter Malan, Zubayr Hamza, Anrich Nortje, Dane Paterson, Vernon Philander, Dwaine Pretorius, Kagiso Rabada, Temba Bavuma, Andile Phehlukwayo, Beuran Hendricks, Keegan Petersen.
The Proteas went down by 28 runs in a high-scoring decider in the third and final one-dayer on Wednesday, coming up short in their run chase after the tourists had posted 320-7.
Bavuma suffered a strained hamstring while batting and will not be available for the first T20 contest on Saturday, which takes place at the Wanderers Stadium in Johannesburg and will play no part in the series.
Heinrich Klaasen will lead the Proteas in the absence of batsman Bavuma, while the in-form Rassie van der Dussen is undergoing treatment on a quad muscle strain and Dwaine Pretorius misses out with a fractured rib.
Reeza Hendricks is also absent following the recent birth of his first child, with Quinton de Kock, David Miller, Kagiso Rabada and Anrich Nortje playing in the Indian Premier League.
Aiden Markram, Andile Phehlukwayo, Daryn Dupavillon and Wiaan Mulder have been retained from the ODI squad.
Pakistan, meanwhile, will be hoping for further white-ball success, having come out on top by a 2-1 scoreline when they hosted their opponents in T20 action earlier this year.
They have added Fakhar Zaman to their squad following his outstanding form in the 50-over fixtures on South African soil.
The opening batsman followed up his 193 in a losing cause in the second game last Sunday with a crucial knock of 103 in the winner-takes-all showdown, with back-to-back centuries moving him up to number 12 in the ICC rankings.
However, Shadab Khan is ruled out due to a fractured toe. The all-rounder will be sidelined for a month, meaning he will also miss the upcoming tour to Zimbabwe. Zahid Mahmood has been named as his replacement for the T20 games on that trip.
Opportunity knocks in absence of Proteas stars
South Africa have failed to win their last five series' in the shortest format and you have to go back to the 2019 whitewash of Sri Lanka for their last triumph.
Miller was man of the series in that 3-0 triumph but the dangerous batsman is among the key absentees for the Proteas' next assignment.
With a T20 World Cup to come in India this year, the players who get their opportunity must grasp it and stake a claim for a place in the squad.
Will Fakhar get his chance?
The left-hander's twin hundreds boosted his career average in ODI action to 49.17. However, his T20 record at the highest level is not so hot, as he has averages 22.05 in his previous 40 appearances.
Pakistan are not short of options to bat at the top of the order, either. Captain Babar Azam has tended to open the innings, while Mohammad Rizwan scored a century - just his country's second in the format - when batting there in the home series against South Africa earlier this year.
After a heavily interrupted first day that saw just 15 overs played, both sides took a slower approach at Queens Park Oval on Thursday.
De Zorzi, who started the day on 32, was up to 78 by lunch as the Proteas steadily added to their figures before he was dismissed by Jomel Warrican (3-66).
Tristan Stubbs (20) and Ryan Rickelton (19) were both left frustrated by Kemar Roach (2-53), though Bavuma managed to add some gloss, hitting 86 off 182 balls, including seven fours, before Jaylen Seales took him (2-57).
Despite a slow start, West Indies conceded only 20 runs in 12 overs against Kyle Verreynne and Wiaan Mulder before the former was taken by Jomel Warrican, who also got Keshav Maharaj for a duck.
South Africa managed to avoid a shaky end to the day, with Mulder's 37 not out helping them edge towards the 350 mark ahead of the third day.
Data Debrief: Proteas show patience
De Zorzi scored just his second half-century for Proteas, getting it against the same opponents as his first when he scored his career-best 85 at Centurion in January.
West Indies struggled with the ball for large parts, something they will want to improve on day three, though Roach's two wickets took him to 272 in Test cricket.
Bavuma has not played for the Proteas since a crushing defeat in the third Test against India in Ranchi last October.
The diminutive batsman was dropped from the squad after being omitted for the first Test against England, and he was challenged to go away and make first-class runs for the Lions.
Bavuma responded by making a career-best 180 against the Dolphins last week and will feature in Johannesburg at the expense of Hamza as South Africa strive to salvage a 2-2 series draw.
Rassie van der Dussen will move up the order to number three in the absence of Hamza, who has made only 39 across five innings since scoring 39 in the first innings of the first Test at Centurion.
South Africa captain Faf du Plessis told reporters on Thursday: "I can tell you that Temba is back in the side.
"The rest, we are still waiting to see what the weather does tomorrow. We don't have 100 per cent clarity on that yet, but that is the one thing that is definite."
A player who will definitely not feature in the fourth Test is Kagiso Rabada. The paceman serves a one-match ban for the excessive celebration of Joe Root's wicket in the third Test that earned him a fourth demerit point.
On another day of limited play due to heavy rain, West Indies struggled through the rest of their innings.
Jason Holder (36) and Kavem Hodge (25) were both taken before Keshav Maharaj (4-76) got his fourth wicket of the innings when Joshua Da Silva (one) was caught.
Kagiso Rabada's 3-56 put West Indies on the back foot, and even Jomel Warrican's 35 could not do much to up their score as they failed to mount a late push.
Jayden Seales was then bowled for four, seeing West Indies finish on 233, trailing the Proteas' score by 124 runs.
South Africa set themselves up nicely for the final day of the Test, with Tony de Zorzi (14) and Aiden Markram (nine) putting the tourists into a 154-run lead at the end of day four.
"Hopefully we can get a full day because that will obviously give us a realistic chance of getting a result," said Bavuma.
"To use the old cliche, we will have to take care of the first hour to set it up and if it's going our way, then we can throw caution to the wind to see what happens.
"But it's imperative that we set it up in that first hour."
De Zorzi and Markram will be looking to keep the pressure on when they resume play at 30-0 on Sunday at Port of Spain.
Earlier this week, the 31-year-old left-hander was named among the final 13-man Test squad that will compete against South Africa. His selection marked a two-and-a-half-year absence from the team, despite some believing the player to be among the region’s top talents.
Powell, who last represented the West Indies in 2018, during the team’s series against Bangladesh, was in contention for selection to the team last year but failed a fitness test in May.
With several first-string players opting out of the Bangladesh tour earlier this year, he was certainly favourite to claim a spot in the squad but was declared to not have met the fitness standard required by the Cricket West Indies (CWI) selection panel. Both the player and the Nevis Cricket Association (NCA) rejected the claims and insisted the batsman had in fact met the required fitness standard. Having been given another chance to shine, Power is, however, eager to claim the opportunity.
“I’ve been out of the team for two and half years now and I’ve counted each month I was not on it,” Powell told members of the media.
“So, it’s obviously a great feeling to be back, but being back is just the start. Obviously, now when I get my opportunity I have to go out and perform and cement my spot,” he added.
Stokes’ comeback could not have come at a better moment for a side whose title defence is on the rocks after a shock defeat to Afghanistan left them with a single win to their name.
The charismatic Test skipper suffered a hip injury during England’s warm-up week in Guwahati and has been sidelined ever since, but has given himself the green light to face the Proteas in Mumbai on Saturday.
Speaking before a training session at the Wankhede Stadium that will double up as a final vigorous fitness test, Stokes told BBC Radio’s Test Match Special: “It was a frustrating little niggle to get before the tournament but I have worked very hard to get back to where I am and making myself ready to be available for selection.
“We have had a few days off since the last game and first training session here in Mumbai. I’ll give it a good push but, yes, I think everything is pretty good. I am in a good place.”
It may be tempting to view Stokes as a saviour riding to the rescue – a role he has performed plenty of times over the course of his career, not least in the 2019 World Cup final – but he distanced himself from the idea.
Responding to the weight of expectation that will follow him on to the field, which has only grown with England’s struggles so far, he said: “I deal with it pretty easy to be honest, because I know I am one person in a team sport.
“No one looks to one person in this team to inspire them or anything like that. It is not the case that if I do come in then all of a sudden we are going to do well. It is just one of those things that gets spoken about a lot but I don’t read into too much.
“Everyone that walks out on to that field for England is a match-winner and can do something individually that can win us a game. We just need to tone it down a bit on me coming back in.”
The tourists won by 189 runs, claiming the 10th wicket in the Proteas' second innings with just over half an hour left to play on day five, as Stokes, who had previously shone with the bat, took the last three wickets in dramatic fashion.
With 26 overs remaining, it looked like the hosts would bat out the day for a draw with Quinton de Kock and Rassie van der Dussen well set and their team on 237-5
But De Kock fell for 50 after a poor shot off Joe Denly before Van der Dussen's 194-minute, 140-ball innings for just 17 ended tamely when he was caught off Stuart Broad down the legside.
Debutant Pieter Malan made 84 after surviving for 288 deliveries, but Stokes helped England prevail and gave coach Chris Silverwood his first Test win in four attempts despite largely being without the injured James Anderson after lunch.
There are two more Tests to come in the four-match series, with the next contest in Port Elizabeth starting on January 16.
Starting the day on 126-2, Keshav Maharaj soon fell for two in the third over, Anderson dismissing him plumb lbw, with the nightwatchman not even waiting for the umpire's finger.
That brought Proteas captain Faf du Plessis to the crease for what the hosts hoped would be a match-saving partnership with Malan.
The skipper, so often his side's final-innings hero, moved on to 19 but got out in poor fashion, giving his wicket away poorly when he swept straight to Denly at square leg off Dom Bess.
That meant South Africa were four down at lunch and the crucial wicket of Malan early in the second session, Sam Curran forcing an edge to second slip where Stokes was waiting gratefully, appeared to have the tourists in control.
The hosts desperately needed a partnership and it arrived through De Kock and Van der Dussen, who managed well as the 32 overs after lunch went for just 55 runs and one wicket.
But just as it looked like South Africa were comfortable, De Kock, who brought up his fifty with a four off Curran, could not believe what he had done when he sent a long hop from Denly straight to Zak Crawley.
England then saw a field change pay immediate dividends, Anderson catching Van der Dussen at leg gully before Stokes (3-35) found the edge of Dwaine Pretorius with captain Joe Root taking a smart catch at slip.
Anrich Nortje went for a golden duck next ball, Crawley keeping his cool in the slips to make the catch at the second attempt while on the ground.
And Vernon Philander was the last man to fall as he fended Stokes to gully, ending the retiring star's attempt to see South Africa through to the close at his home stadium.
Rabada will miss the last match of the series at The Wanderers after being sanctioned for his reaction to dismissing Joe Root on day one of the third Test at St George's Park.
The paceman roared in celebration after bowling the England captain and that resulted in him being found guilty of a level one breach of the ICC code of conduct.
It earned Rabada a fourth demerit point in a two-year period, a tally that triggers a one-match ban.
Boucher felt Rabada should have known better, but suggested the punishment was harsh after watching England take charge in Port Elizabeth by posting 499-9 declared before the Proteas were reduced to 60-2 in reply on Friday.
"I think KG has a bit of a history, he probably shouldn't have done it, but it is what it is," said the South Africa head coach.
"The level one is a slap on the wrists but unfortunately he's got too many demerit points. We played in days when bowlers used to swear at batsmen, you want to be nice and aggressive.
"He didn't look at Joe Root, but it's about how you determine the laws. KG is best when he's nice and aggressive. We'll get him to run to square leg rather than the batter. But the laws are there and you have to abide by them.
"I wasn't aware of all the demerit points [Rabada has] and how the whole system works, so to hear this morning he's going to be banned for the final Test is a massive blow for us.
"He's a world-class performer, especially at The Wanderers, where I think he would be very effective."
The former South Africa wicketkeeper-batsman added: "We spoke to the match referee [on Thursday] and we did voice our concerns over the rule and a couple of variations of the rule.
"It's a tough one to gauge about excessive celebrations in the area of the batter and making contact with the batter.
"I don't feel that he made any contact with the batter whatsoever. Yes, he was in his space, but the two put together there is probably different ways you can look at it. Bottom line is the match referee has made up his mind."
Despite a late wobble with the bat, England claimed victory with 40 balls unused on Sunday to ensure the three-match series finished level at 1-1, the second game in Durban having been washed out.
Boucher felt his team were "30 to 40 runs short" when making 256-7 with the bat, while they then made an abysmal start with the ball as Jonny Bairstow (43 off 23 balls) got stuck into Lungi Ngidi and Beuran Hendricks.
Although South Africa fought back, dropped chances from Joe Denly and Tom Banton hindered their hopes of turning things around.
"We were probably 30 or 40 runs short and then, with the ball, we just started off really, really poorly and we were playing catch-up after that," said Boucher in a news conference.
"We had chances and we didn't take our opportunities. When you are 30 to 40 runs short, you have got to bowl well, especially up front, and you've got to take your opportunities.
"We didn't do that. That's why we lost."
South Africa and England both rested frontline players for the ODI series, and Boucher indicated the Proteas would continue to experiment in their next 50-over matches against Australia.
"It's a long time until the next [50-over] World Cup, so we can afford to do that," he added.
"There are a lot of good things that happened and a couple of things we need to work on, obviously, but it is quite difficult to judge over two games.
"We'll probably use the next three games against Australia to find out some answers and ask some questions. We do believe we're going in the right direction."
Former skipper Faf du Plessis is likely to return against Australia, though, after being rested and replaced as captain by Quinton de Kock for the ODI and T20 series with England.
"We feel at this point in time he [Du Plessis] needs a bit of a break away from the game," Boucher explained.
"I would like to think, against Australia, the rest will be enough and they [Du Plessis and Kagiso Rabada] can come back and play."
The Proteas suffered a nine-wicket defeat in the third and final Test of their tour of England at The Oval on Monday, losing the series 2-1.
Boucher took on the role in December 2019, signing a four-year deal and going on to secure 11 wins in Test matches, as well as 12 ODI and 23 T20I victories.
South Africa are currently second in the ICC World Test Championship table, despite their loss in England, and Boucher's last games in charge will come at the T20 World Cup in Australia, which runs from October 16 to November 13 later this year.
A statement from CSA on Monday outlined that Boucher had resigned to "pursue other opportunities in line with his future career and personal objectives".
"While Cricket SA greatly regrets that Mr Boucher is unable to see out the term of his contract, it respects his decision and wishes him all the best in his future endeavours," the statement added.
The former Proteas wicket-keeper earned 147 Test caps during his playing days between 1997 and 2012, scoring 5,515 runs at an average of 30.30.
CSA Chief Executive Pholetsi Moseki thanked Boucher for his efforts in the role, saying: "We would like to thank Mark for the time and effort he has invested in South African cricket as the head coach over the past three years.
"He has helped navigate us through some rough waters following the departures of so many senior players through retirement and has helped lay some strong foundations for the next generation of Proteas.
"We are extremely grateful to him for the work he has done and would like to wish him well with the next chapter of his career."
CSA also confirmed it "will in due course announce its intentions regarding a successor to Mr Boucher".
Cricket South Africa announced following the Test series defeat to England this week Boucher was set to step down to "pursue other opportunities in line with his future career and personal objectives".
The 45-year-old has quickly secured a new role in the Indian Premier League, joining Mumbai for the 2023 season.
"It is an honour and privilege to be appointed as head coach of MI," Boucher said in an Indians statement.
"Their history and achievements as a franchise clearly put them up there as one of the most successful sporting franchises in all of world sport. I look forward to the challenge and respect the need for results.
"It's a strong unit with great leadership and players. I look forward to adding value to this dynamic unit."
