World number one Novak Djokovic was full of praise for his Serbia Open semi-final conqueror Aslan Karatsev but bemoaned his own "low level" performance.

Karatsev got past Djokovic in the longest match of the 2021 ATP Tour in Belgrade, triumphing 7-5 4-6 6-4 on Saturday.

The match went for three hours and 25 minutes, with the Russian securing a spot in Sunday's final against 10th ranked Matteo Berrettini.

The Serbian had beaten Karatsev in the Australian Open semi-finals two months ago, with the 27-year-old Russian, who is now ranked 28th, returning the favour.

"From my side, I played on quite a low level, in my opinion," Djokovic said.

“[I had] some flashes of good quality tennis. I was fighting. That is a positive.

"I was really trying all the way [and] the crowd was great. They carried me and tried to lift me up, all the way to the end.

"Because of them, I think I won the second set. Unfortunately in the third, he was just the better player in the decisive moments. I had my chances, but that is sport."

Djokovic was gracious in defeat, offering a thumbs up immediately after Karatsev secured victory along with complimentary words to his opponent who saved 23 of 28 break points.

"Karatsev showed a lot of courage and that is why I gave him the thumbs up," Djokovic said.

"I felt like he deserved to win… Once the final point is done, there is never bad blood. We are rivals on the court, but I don’t hate anybody. I can’t be upset with him if he beat me.

"I have to be upset with myself and question why I lost the match. Whoever beats me deserves the credit and I gave him that.

"I lost to a better player who was just more courageous. He went for his shots at the right time and it worked for him."

Aslan Karatsev secured a stunning career-best victory over home favourite Novak Djokovic to set up a Serbia Open final against Matteo Berrettini.

Karatsev showed astonishing defiance to beat the world number one 7-5 4-6 6-4 in the longest ATP Tour match of the year on Saturday.

The third seed from Russia saved 23 of the 28 break points he faced as his aggressive approach paid off, toppling the 18-time grand slam champion in a contest that lasted three hours and 25 minutes.

It was sweet revenge for Karatsev, who was beaten by the legendary Serbian at the semi-final stage of the Australian Open two months ago.

Djokovic had won 11 matches in a row in his homeland, but bowed out despite being 2-0 up in the first two sets as a solitary break in the decider ended his run.

Karatsev, the world number 28, said: "It was a long, tough match [against a] tough opponent.

"You have to put [in] like 200 per cent to beat this guy, it's like playing against a wall. And he also made some good shots.

"He doesn't give you any free points. He always makes you play and you have to be always there because once you miss a couple of shots, he just takes it very quickly. That’s how I lost the second set."

Berrettini secured his place in the final with a 6-1 6-7 (5-7) 6-0 victory over lucky loser Taro Daniel.

Second seed Berrettini only lost six points in the last set after Daniel came from a break down in the second before winning a tie-break to take the second semi-final the distance.

Heading into Sunday's final, Karatsev and Berrettini have never previously faced each other on the ATP Tour.

Rain curtailed much of Monday's schedule at the Monte Carlo Masters but it could not prevent Aslan Karatsev from continuing his hugely impressive start to the season.

Karatsev, a surprise Australian Open semi-finalist and a champion in Dubai last month, overcame Lorenzo Musetti, the Italian teenager who was a semi-finalist in Acapulco in March, in straight sets after a four-hour rain delay.

He went into that interruption with a 4-3 lead in the first set and duly polished off the next two games on his return to the court.

The Russian sent down 23 winners as he completed a 6-3 6-4 win in 88 minutes, his last a cross-court backhand that set up a second-round meeting with Stefanos Tsitsipas.

"It was a really tough match [for] my first match of the season on clay [with] tough weather conditions," said Karatsev.

"We started in the morning [and] I started pretty well, I broke him and then the court was getting heavy, the ball was heavy.

"It is tough to play against him. [He is] really fit, [he] runs a lot and gives everything back, so you have to build the point by yourself and close the point by yourself."

There were mixed fortunes for Australians Alex de Minaur and John Millman in Monaco.

De Minaur went down to a surprise straight-sets defeat to Alejandro Davidovich Fokina but Millman broke Ugo Humbert four times in a 6-3 6-3 win.

Next for Millman is either Felix Auger-Aliassime or Cristian Garin, whose first-round contest was among those unable to finish because of the inclement weather on the Cote d'Azur.

Tommy Paul also progressed to the next round, with five matches on court when play was cancelled for the day.

Stefanos Tsitsipas battled through to the Miami Open round of 16 and he was joined by Andrey Rublev on Monday.

Greek star and second seed Tsitsipas got the better of 2014 US Open runner-up Kei Nishikori in Miami.

Rublev continued his fine 2021 with a straight-sets demolition of Marton Fucsovics at the ATP 1000 tournament.

In-form Aslan Karatsev, however, bowed out following a surprise loss to Sebastian Korda.

TSITSIPAS HALTS NISHIKORI

Despite a mid-match wobble, Tsitsipas overcame Nishikori 6-3 3-6 6-1 to reach the fourth round.

Former world number four Nishikori forced a deciding set but Tsitsipas withstood the Japanese's comeback.

Tsitsipas, who hit 32 winners, will meet Lorenzo Sonego for a place in the quarter-finals after the 24th seed defeated Daniel Elahi Galan 7-6 (8-6) 6-3.

RUBLEV STAYS HOT

Russian fourth seed Rublev made light work of Fucsovics 6-2 6-1 in just 52 minutes.

Rublev leads the ATP Tour with 18 victories this season after eliminating the in-form Hungarian, ahead of top seed Daniil Medvedev (16-2).

The result secured a third win for Rublev over 29th seed Fucsovics this month.

"I was laughing, because of [the] situation and plus Marton also told me, 'I don't want to see you. I don't want to see you'," Rublev said, cracking a laugh. "[It was] just a situation that [was] fun, and I feel sorry."

Awaiting Rublev is 2014 US Open champion and former world number three Marin Cilic, who beat Lorenzo Musetti 6-3 6-4.

KARATSEV CONQUERED

For only the third time this year, Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev tasted defeat following a 6-3 6-0 loss at the hands of Korda.

American sensation Korda became the first player outside the top five to beat Karatsev this year, with the latter's previous two losses coming against world number one Novak Djokovic and world number four Dominic Thiem.

"It is super special [to reach the Round of 16], especially playing a guy who was as hot as he was," said Korda. "I just took the tactics that I used [against him] at Roland Garros and it worked out really well today."

Diego Schwartzman stands in the way of Korda and the quarters after the fifth seed accounted for Adrian Mannarino 6-1 6-4.

Elsewhere, Denis Shapovalov – the sixth seed – was upstaged by Hubert Hurkacz 6-3 7-6 (8-6).

Another Canadian awaits Hurkacz after 12th seed Milos Raonic was a 6-4 7-5 winner against Ugo Humbert.

Stefanos Tsitsipas continued his strong run of form en route to the Miami Open third round, while Aslan Karatsev's maintained his fairytale run in 2021.

Greek star Tsitsipas flexed his muscles in a straight-sets win over Damir Dzumhur on Saturday.

Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev enjoyed a victorious Miami debut.

Andrey Rublev, Diego Schwartzman, Denis Shapovalov, Marin Cilic and Milos Raonic also progressed at the ATP 1000 tournament.

TSITSIPAS STAYS HOT

World number five Tsitsipas eased past Dzumhur 6-1 6-4 in his first appearance since losing in last week's Mexican Open final.

Tsitsipas (15-4) became the third player to reach 15 wins this season, the second seed following in the footsteps of Russian duo Rublev (17-3) and Daniil Medvedev (15-2).

"It was a great match, especially against a guy that I probably don't have a good record playing against in the past," said Tsitsipas. "I started the match very strong, breaking him twice and taking a big lead in the score, and I think the things worked out by themselves after that."

Tsitsipas will face Kei Nishikori after the Japanese outlasted Aljaz Bedene 7-6 (8-6) 5-7 6-4.

NO STOPPING KARATSEV

Karatsev's Miami Open debut ended in a 6-4 6-3 win for the 17th-seeded Russian over Mikhail Kukushkin.

Already in the ATP's top 100 and set to keep climbing, Karatsev broke serve four times en route to the next round, where Sebastian Korda awaits after upstaging 10th seed Fabio Fognini 1-6 6-4 6-2.

"Of course it gives me confidence to win my first title, but you arrive here and it’s a different surface and new tournament," said Karatsev, who ended last season ranked 112th before bursting into the top 30 behind his semi-final run at Melbourne Park. "So you try [to think of it] as a new tournament and new place, but of course it gives me a lot of confidence."

Karatsev owns a 13-2 record this year, with his only two losses coming against world number one Novak Djokovic and US Open champion Dominic Thiem.

RUBLEV ROLLS ON

Fourth seed Rublev has proven to be remarkably consistent, highlighted by his crushing 6-1 6-2 rain-interrupted victory against Tennys Sandgren.

Having equalled his previous best run in Miami, Rublev will play 29th seed Marton Fucsovics who took down Thanasi Kokkinakis 7-6 (7-3) 6-7 (4-7) 6-4.

Rublev has won a Tour-leading 17 matches this year.

Elsewhere, fifth seed Schwartzman was a 6-3 6-3 winner against Yasutaka Uchiyama, Shapovalov – the sixth seed – trumped Ilya Ivashka 6-7 (5-7) 6-4 6-4 in a marathon, 12th seed Raonic accounted for Jordan Thompson 6-2 6-1, former US Open winner Cilic surprised 13th seed Christian Garin 3-6 7-5 7-6 (7-5), while 15th seed Alex de Minaur was eliminated.

Aslan Karatsev captured the first ATP Tour title of his career as the late-blossoming Russian triumphed in the final of the Dubai Tennis Championships.

At the age of 27, and with little warning, Karatsev has hurtled from obscurity before tennis went into lockdown 12 months ago to real prominence.

A 6-3 6-2 victory over South African Lloyd Harris on Saturday gave him a trophy for his efforts and he will enter the top 30 on Monday, having never had a double-digit ranking before this season.

Karatsev reached the Australian Open semi-finals last month, having had to win three qualifying rounds to make the main draw, and it took Novak Djokovic to stop that charge in Melbourne.

Now Vladikavkaz-born Karatsev is back in another winning routine, with Andrey Rublev, Jannik Sinner and Dan Evans having figured among his victims en route to the Dubai final.

The first-time champion said on Amazon Prime: "I am super happy. It was a tight match. [I was] really nervous. I want to congratulate my opponent for the final [run]. He did a great week. Every final is different, so I am happy that I won."

Karatsev had some promising results at Challenger Tour level last year but had never shown form on the main circuit until the start of 2021, and suddenly he looks a major force to be reckoned with.

He said of the rush of success: "You never know when it is coming. I did a good job with my team, with my coach and it has happened now."

Andrey Rublev's ATP 500 winning streak came to an end at the hands of Aslan Karatsev on a history-making day at the Dubai Tennis Championships.

Rublev had won 23 consecutive matches at this level, second only to Roger Federer (28), but Karatsev finally ended the Russian's remarkable run to progress to his first ATP singles final.

Karatsev, who incredibly went from qualifying to the semi-finals of the Australian Open this year, defeated his compatriot 6-2 4-6 6-4.

He became the first Wild Card to reach the final since Thomas Muster in 1997, doing so by hitting 41 winners and forcing 16 break points – of which he won four – during two hours and 12 minutes on court.

"It was a really tight match [against a] tough opponent," Karatsev said in his on-court interview.

"It was an unbelievable performance [from Andrey]. He didn't lose a match at an ATP 500 in [one year]. Everything was decided in one or two points, I feel happy."

The championship match will be between two first-time Dubai finalists after Lloyd Harris stunned Denis Shapovalov in the other semi-final.

World number 81 Harris, who overcame top seed Dominic Thiem, 14th seed Filip Krajinovic and former US Open finalist Kei Nishikori to reach the last four, came from a set and 4-2 down to defeat world number 12 Shapovalov.

He prevailed 6-7 (5-7) 6-4 7-6 (8-6) to reach a maiden ATP 500 final and become the first qualifier to reach the showpiece in Dubai.

"I don't have many words right now. I am super happy with that win," Harris said on court afterwards.

"Being a set and 2-4 down is mentally and physically a little bit troublesome for me, but I found my best tennis from there. I am just extremely happy with the result right now."

Novak Djokovic ended Aslan Karatsev's dream run to reach his ninth Australian Open final on Thursday.

Djokovic, who has been dealing with an abdominal injury in Melbourne, brushed past qualifier Karatsev 6-3 6-4 6-2 in their semi-final on Rod Laver Arena.

The world number one has won the Australian Open every time he has reached the semi-finals, and he is on track again ahead of facing either Daniil Medvedev or Stefanos Tsitsipas in Sunday's decider.

Djokovic moved into his 28th grand slam final – a tally bettered only by Roger Federer (31) – as he targets an 18th major title.

Karatsev held his own in the early baseline exchanges and dug himself out of a 0-30 hole in the sixth game.

But he could not deny Djokovic in his next service game, broken to love when he pulled a backhand wide as the Serbian won 10 straight points and the set.

Djokovic broke again in the third game of the second set following a Karatsev double fault, and a fortunate net cord saw him into a 4-1 lead as he took complete control.

Karatsev got one of the breaks back and pushed for the other, but Djokovic – who had won all 19 of his previous meetings with qualifiers at grand slams – closed out the second set.

Just as Karatsev seemed to be working his way back into the contest and the duo exchanged breaks to begin the third, Djokovic took a 3-2 lead as he won the final four games of the match.

Data Slam: Age still no barrier for Djokovic
Djokovic became the first man in the Open Era to reach three Australian Open finals after turning 30. The 33-year-old has dominated in Melbourne, and his run continues.

WINNERS/UNFORCED ERRORS
Djokovic – 30/14
Karatsev – 24/30

ACES/DOUBLE FAULTS
Djokovic – 17/2
Karatsev – 6/2

BREAK POINTS WON
Djokovic – 6/7
Karatsev – 2/5

Aslan Karatsev said finding stability off the court has helped him become the revelation of this year's Australian Open after the qualifier marched on to the semi-finals.

The Russian became the first qualifier to reach the last four of a major since Vladimir Voltchkov, famously in borrowed shorts, did so in 2000 at Wimbledon.

It was Pete Sampras who eventually blew away Voltchkov's threat at the All England Club on his way to another title.

And it turns out there is a connection between Karatsev and Voltchkov, with both men now calling Minsk their home.

But whereas Voltchkov is Minsk born and bred, Karatsev has taken a roundabout route to setting down roots in the capital of Belarus.

He explained on Tuesday how he was born in the Russian city of Vladikavkaz before moving as a toddler to Israel with his family and living there until the age of 12, when he and his father returned to Russia, spending time in the city of Taganrog.

Tennis took him to training bases in Moscow, then Halle in Germany, Barcelona, and finally Minsk.

It is in Minsk that Karatsev has linked up with former ATP professional Yahor Yatsyk, a man only one year his senior but already settling into coaching.

As Grigor Dimitrov succumbed to injury and slid to a four-set defeat against Karatsev on Tuesday, the unlikely figure in the final four reflected on his long road to this point.

"Yes, I was moving I would say too much," Karatsev said of his nomadic existence.

"In the end I found a coach, Yahor Yatsyk, and this is the right guy for me. He's helped me a lot, more the mental part, and then of course there is the technical stuff as well.

"I like to work with him. We're living in Minsk. We're practicing there."

Karatsev is the lowest-ranked man to reach a grand slam semi-final since Goran Ivanisevic, who won Wimbledon in 2001 on a wildcard entry while ranked 125th in the world.

His charge through the draw makes him only the second qualifier to advance to the Australian Open last four, after Bob Giltinan in December 1977.

"Of course it's amazing that I passed to the semi-finals from qualifying," Karatsev said. "I'm just trying to enjoy the moment and not thinking about that too much and playing from round to round."

He and Yatsyk set the goal of reaching the top 100, which Karatsev had not managed before getting to Melbourne.

Before this fortnight he stood at 114th in the rankings, but he will hurtle to a double-digit ranking next week.

"I think the key is to find the right team, the right coach that I found. I was really lucky to find him," Karatsev said.

"We just met in one tournament. We were saying, 'Okay, let's try to work together', and it's really a big luck that we started to work together and I have a good team around me."

Before he encountered Yatsyk, who as a player did not crack the top 1,000 in singles, Karatsev had a brief moment when he wondered if he might not make the grade.

"There was a time when I was injured that was a difficult time for me because I recovered after the injury, and then 2017 started, and I started to play again, and again I felt the knee," Karatsev said. "I said, 'Whoa.' I quit again for two and a half months, almost three, and I think this is the most difficult part."

Aslan Karatsev's Cinderella story and historic run continued after sensationally reaching the Australian Open semi-finals as Grigor Dimitrov struggled dramatically with injury on Tuesday.

Former world number three Dimitrov won the opening set and was on track to move through in Melbourne, but he faded alarmingly due to a lower back problem.

Karatsev capitalised to oust his much-more fancied opponent – who was barely able to walk afterwards – 2-6 6-4 6-1 6-2 on Rod Laver Arena, the Russian qualifier and world number 114 becoming the first man in the Open Era to reach the semi-finals on his grand slam debut.

The unheralded 27-year-old also became just the second qualifier to advance to the Australian Open last four after Bob Giltinan in December 1977 as defending champion Novak Djokovic or Alexander Zverev await.

Dimitrov was aiming to reach his second Australian Open semi-final and the final four of a slam for the fourth time in his career, and the Bulgarian star started well.

After being broken in the third game, 18th seed Dimitrov put the set back on serve immediately as he took control of proceedings.

Dimitrov fired down four aces, won 82 per cent of his first serves, hit six winners and made just five unforced errors, while Karatsev's unforced-error count hit 19.

But just as Dimitrov – who had not dropped a set en route to the quarters – looked like the man to beat, he wilted in remarkable scenes as Karatsev won the second set to level the match.

Dimitrov's first-serve winners dipped to 69 per cent – his second serve extremely problematic – while his unforced errors grew to 15 in the second set – and Karatsev took advantage.

The third set was a write-off for Dimitrov, who headed to the locker room for medical treatment after Karatsev cruised to a two-sets-to-love lead.

There were remarkable scenes in the third set, Dimitrov virtually conceding as he was unable to keep up with Karatsev due to the injury.

Dimitrov, who only won 12 points in the third set as he was unable to keep up with Karatsev or generate any power on his serve, emerged for the fourth set but, while he tried to will himself on, it only delayed the inevitable in sad scenes.

Data Slam: Karatsev joins Russian club
Karatsev became the fourth Russian man to reach the Australian Open semis in the Open Era, after Aleksandar Metreveli  (1972),  Yevgeny  Kafelnikov  (1999-2000)  and  Marat  Safin  (2002, 2004-05). He is also the lowest-ranked man to reach the semi-finals of a major since Goran Ivanisevic (125) at Wimbledon in 2001.

WINNERS/UNFORCED ERRORS
Dimitrov – 21/34
Karatsev – 34/44

ACES/DOUBLE FAULTS
Dimitrov – 9/7
Karatsev – 9/6

BREAK POINTS WON
Dimitrov – 4/14
Karatsev – 8/11