The Kings, after winning the toss and batting first, posted 177-7 from their 20 overs.
Avishka Fernando was the main contributor for the three-time champions with 59 from 48 balls while Pathum Nissanka hit 51 off 33 balls.
Fernando’s innings included seven fours and a six while Nissanka hit six fours and two sixes.
Captain Charith Asalanka also contributed a 15-ball 33 against 3-34 off four overs from Zahoor Khan and 2-23 from four overs from Dwayne Pretorius.
The Marvels then used all of the 120 balls available to them to successfully chase down their target.
Alex Hales led the way with 65 off 47 balls including seven fours and two sixes while Captain Niroshan Dickwella made 47 off 27 balls including eight fours and a six as Galle reached 179-5 off 20 overs.
Janith Liyanage also made a crucial 13-ball 25 for Galle. It eventually came down to them needing three runs off the last ball, a ball that Sahan Arachchige hit for four to seal the win.
Fabian Allen took 2-33 from his four overs for the Kings.
Full Scores:
Jaffna Kings 177-7 off 20 overs (Avishka Fernando 59, Pathum Nissanka 51, Charith Asalanka 33, Zahoor Khan 3-34, Dwayne Pretorius 2-23)
Galle Marvels 179-5 off 20 overs (Alex Hales 65, Niroshan Dickwella 47, Janith Liyanage 25, Fabian Allen 2-33, Avishka Fernando 2-40)
After winning the toss and choosing to bat first, the Capitals were reduced to just 104 all out off 18.2 overs.
Sikandar Raza (22), Roelof van der Merwe (21), David Warner (16) and Rovman Powell (10) were the only Capitals batsmen to scratch double figures.
Theekshana produced a masterful spell of bowling to take 4-20 from his four overs while being well supported by Daniel Sams’ 3-28 off four.
The Warriors then needed only 13-1 overs to reach 105-1 and secure their third win in five games.
Charles top-scored with an unbeaten 43 off 33 balls including four fours and one six. Joe Denly was Charles’ partner at the crease with an unbeaten 23 off 16 balls. Earlier, Niroshan Dickwella made a 30-ball 37.
Fletcher hit a top score of 69 to help the Falcons produce 187-9 from their 20 overs after being put in to bat by the Marvels.
His knock lasted 43 balls and included six fours and four sixes. He got good support from opening partner Dinesh Chandimal who made 32 while Angelo Mathews and Ramesh Mendis chipped in with 29 and 28, respectively.
Prabath Jayasuriya took 3-30 from his four overs for Galle.
The Marvels then took 19.2 overs to reach 188-2 and secure a comfortable victory.
Alex Hales was the catalyst behind the successful chase with 86* off 55 balls including seven fours and four sixes while Bhanuka Rajapaksa finished 46* off 25 balls including five fours and a pair of sixes.
Captain and wicket-keeper Niroshan Dickwella also chipped in with 25.
Fletcher also took 1-11 from two overs with his part-time leg-spin.
The Marvels are now second in the points table after six games, level on eight points with leaders Jaffna Kings.
The Falcons have two wins from six games and sit last on the six-team table.
Full Scores:
Kandy Falcons 187-9 off 20 overs (Andre Fletcher 69, Dinesh Chandimal 32, Angelo Mathews 29, Ramesh Mendis 28, Prabath Jayasuriya 3-30, Dwayne Pretorius 2-37)
Galle Marvels 188-2 off 19.2 overs (Alex Hales 86*, Bhanuka Rajapaksa 46*, Niroshan Dickwella 25)
Mathews spent 10 hours at the crease to make an imperious unbeaten 200 with support from Dhananjaya de Silva and Niroshan Dickwella, who each made 63 in the tourists' 515-9 declared.
Sri Lanka will resume on the final day looking to make quick inroads with the ball after Zimbabwe reached stumps on 30 without loss, trailing by 127.
Mathews had waited since December 2018 to reach three figures in the longest format, but brought up his 10th Test century early on the penultimate day after Sri Lanka resumed on 295-4.
Dhananjaya had a sixth Test half-century when he went through for a single after being struck on the glove by a Donald Tiripano, but a fifth-wicket stand of 98 ended when he drove Victor Nyauchi (3-69) to Prince Masvaure at mid-on.
That was the only wicket to fall in the morning session and the Zimbabwe bowlers endured more frustration after lunch as Mathews, dropped by wicketkeeper Regis Chakabva on 108, and Dickwella increased the lead.
Dickwella was put down by Sean Ervine on 45 and struck only three boundaries in his 15th Test half-century before being trapped lbw by Sikandar Raza, halting a stand of 126.
Raza (3-62) saw the back of Suranga Lakmal and Lasith Embuldeniya in consecutive deliveries, but Mathews went on to become the first Sri Lankan man for five years to score a Test double-hundred.
Kasun Rajitha's dismissal prompted Dimuth Karunaratne to declare, but Sri Lanka were unable to end the day on a high note as Masvaure and Brian Mudzinganyama saw Zimbabwe through to the close unscathed.
The players were in Durham preparing for the first of three ODIs against the world champions last month when they left the team hotel to visit the city centre despite strict COVID-19-related rules.
Batsmen Mendis and Gunathilaka and wicketkeeper-batsman Dickwella were sent home and have now been hit with strong sanctions.
The executive committee of Sri Lanka Cricket took into account recommendation made by an independent panel of inquiry before handing down a 12-month ban from playing at international level and a six-month domestic suspension.
They were also given a further one-year ban, which is suspended for a two-year period.
Mendis, Dickwella and Gunathilaka have been fined 10million Sri Lanka Rupees (around £36,000) for their indiscretion.
Big scores had gone down as the tournament wore on, but Gladiators' 91 for 5 after being sent in appeared insufficient for the big occasion. It proved to be exactly that, despite Strikers being 7 for 2 in 1.1 overs, with openers Muhammad Waseem and Rahmanullah Gurbaz dismissed cheaply.
Niroshan Dickwella and Asif Ali, the Player of the Match, put the innings back on track, before Dickwella was sent back by Andre Russell for a 12-ball 14. From there on, it was all about Asif and captain Kieron Pollard, who put up 56 runs together without much scoreboard pressure to weigh them down.
Asif scored 48 not out in 25 balls with two fours and four sixes, and Pollard chipped in with 22 not out in 13, with a four and six, as Strikers won the title.
The win was set up by the bowlers, though. Gladiators had a decent opening stand of 28 with Tom Kohler-Cadmore and Nicholas Pooran, the No. 1 and No. 3 on the tournament run-scorers' list, but Narine broke through in the third over with Kohler-Cadmore's wicket for a seven-ball 13. Pooran fell to George Scrimshaw two balls later, and Gladiators were suddenly 28 for 2, which became 36 for 3, 41 for 4, and 57 for 5 after 7.1 overs, with Narine returning 2 for 6 from his two overs without conceding a single boundary.
Russell, who finished with an unbeaten 30 from 18 balls with two fours and two sixes, and David Wiese, 20 not out from 11, with a four and two sixes, completed the innings with some momentum, but it was too few for Gladiators to defend on the night.
The pair added a record 179 for the sixth wicket and Nissanka became the first Sri Lankan to make a century away from home in his first match. He eventually fell to a catch by Kemar Roach from the bowling of off-spinner Rahkeem Cornwall, who ended with 3-137 off a marathon 42.5 overs.
Roach had the best figures of 3-74 off 27 overs to end the match with six wickets – following up his 3-47 off 16 overs in the first innings.
This left the West Indies with a victory target of 375. They reached 34-1 at the close and will require another 341 to win on the final day with nine wickets in hand. Nkrumah Bonner will resume Thursday on 15 not out and with him captain Kraigg Brathwaite on eight not out.
The match resumes on Thursday at 10 am (9 am Jamaica Time).
The decision from Sri Lanka Cricket comes less than six months into the suspension period, and means they are once again eligible for selection in domestic cricket as well as for their national side.
The ban was handed out after the three players were found to have breached COVID-19 bio-bubble protocols during the tour of England last year.
The players were in Durham preparing for the first of three ODIs when they left the team hotel to visit the city centre despite strict COVID-19-related rules.
Batsmen Mendis and Gunathilaka, and wicketkeeper-batsman Dickwella were sent home and hit with strong sanctions.
The executive committee of Sri Lanka Cricket took into account recommendations made by an independent panel of inquiry before handing down a 12-month ban from playing at international level and a six-month domestic suspension.
All three were also fined 10million Sri Lanka Rupees (around £36,000) for their indiscretion.
However, a statement released on Friday outlined that the ban had been lifted, confirming: "Sri Lanka Cricket has decided to lift the one-year suspension imposed on the [three] players from playing international cricket, across all three formats, with immediate effect.
"The latest decision was taken following a request made by the three players to Sri Lanka Cricket to lift the ban imposed on them, pursuant to the conclusion of the LPL 2021. Based on such request, Sri Lanka Cricket obtained a report from the doctor appointed by SLC to provide counselling for the three players during their period of suspension."
Sri Lanka Cricket did also state that if the trio have any further disciplinary breaches in the next two years, the remainder of the suspension will need to be served.
"The lifted suspension will remain suspended for a period of two years, during which the three players' conduct will be closely monitored by the SLC," the release added.
"Accordingly, the three players will be able to engage in playing domestic cricket with immediate effect and will also be available for national selection, subject to complying with mandatory fitness standards."
The three players were in Durham preparing for the first of three one-dayers against England but left the team hotel to visit the city centre against COVID-19-related health guidelines.
A statement from Sri Lanka Cricket on Monday said: "This decision was taken following a preliminary inquiry conducted over a video posted on social media in which the three said players can be seen outside their designated hotel.
"The three players will be suspended from all forms of cricket until the completion of the inquiry."
The trio featured in Sri Lanka's Twenty20 international series against England, which the hosts won with a 3-0 whitewash, and had been expected to be involved in the ODI series.
"The players have been suspended pending a full inquiry, but have confessed to having gone out," Sri Lanka Cricket vice-president Mohan de Silva told Cricinfo.
"They are being recalled [home] from the tour with immediate effect."
Mendis, 26, only made 54 runs in three innings during the T20 series but did top score with 39 in the second T20 in Cardiff while fellow batsmen Gunathilaka, 30, has struggled with knocks of four, three and 19.
Dickwella played the second two matches but the 28-year-old managed just 14 runs with the bat and no catches or stumpings.
The departure of Mendis, Gunathilaka and Dickwella, following an injury to Avishka Fernando has left Sri Lanka has left coach Mickey Arthur with a depleted squad but there are no plans to cancel the series, which starts on Tuesday.
