South Africa 343 for 4 (Amla 110, du Plessis 73*, Pollard 2-64) beat West Indies 204 (Charles 49, Tahir 7-45) by 139 runs
Scorecard and ball-by-ball details
Hashim Amla scored his 23rd ODI hundred and brought up 1000 runs in the format against West Indies as South Africa put on their best batting display and the only 300-plus score of the tri-series so far. But that was only half of how the visitors boosted their hopes of qualifying for the final.
Imran Tahir claimed 7 for 45 - the best ODI returns by a South African bowler, and he also became the fastest to 100 ODI wickets from the country - to deny West Indies, who have never been successful chasing a target over 300.
South Africa bundled West Indies out for 204, secured a bonus point, and topped the table. The result meant the St Kitts' segment of the series ended with all three teams in the same position as they were after the Guyana leg. Australia, South Africa and West Indies have played four matches, won two and lost two.
In the lead up to Wednesday, Amla stressed the need for the top six to take more responsibility. On Wednesday, he stood by those words and shared a 182-run opening partnership with Quinton de Kock. Allrounder Chris Morris, who returned from a hamstring niggle, was promoted to No. 3 and provided a cameo before Faf du Plessis led the late assault. South Africa plundered 105 runs off the last 10 overs.
Although this was the best surface for batsmen in the series so far, West Indies' bowlers lacked control and penetration. Four of their six-man attack conceded more than six runs an over with only the spinners, Sunil Narine and Sulieman Benn, able to hold up an end. The pacemen could not find the right lengths and runs came easily for South Africa.
Amla dominated the early exchanges, outscoring de Kock. The pair brought up 50 in nine overs, 100 at the start of the 18th, and 150 inside the 27th during a chanceless stand. Amla attempted to accelerate further after he brought up his century, off 89 balls. He got low to scoop a ball to the fine-leg boundary, flashed hard and edged one to third man, and eventually holed out to long-off looking for his first six.
The stage seemed set for de Villiers' entrance but Morris was pushed up. It seemed a mistake when, in the next over, de Kock's off stump was taken out by a Jerome Taylor yorker. The left-hander had made 71 off 103 balls. Still, de Villiers did not appear.
Morris struck a flashy 40 off 26, including four boundaries, before he found deep midwicket. De Villiers finally arrived, and along with du Plessis, played Narine out before cutting loose. The pair plundered 64 runs off seven overs to take South Africa over 300. Du Plessis stayed unbeaten with 73 and got them close to 350.
A similar breakneck pace was set by West Indies' openers Andre Fletcher and Johnson Charles as they took advantage of Kagiso Rabada and Wayne Parnell's insistence on bowling short. The score raced to 58 in the first six overs before Tahir was brought on. The legspinner made the first incision at the end of his second over thanks to a stunning catch by Farhaan Behardien on the midwicket boundary. Fletcher swung hard but Behardien grabbed it inches off the ground, with the ball dying on him.
Morris and Tabraiz Shamsi helped Tahir keep West Indies in check. The spinners were exerting their control as Shamsi foxed Charles with a googly that he sliced to long-off. Realising the help on offer, Parnell resorted to offbreaks and bowled Darren Bravo to leave Marlon Samuels having to stage a coup. West Indies needed 254 runs in only 204 balls with seven wickets in hand.
Denesh Ramdin hung around before top-edging a googly from Shamsi to deep backward square leg for 11. Then Tahir took over. He picked up his 100th wicket in only his 58th match when Samuels edged to de Kock, and knocked over all three of West Indies' big-hitting allrounders in the same over. Jason Holder was trapped lbw for 19 off 31, Carlos Brathwaite was handed a golden duck, and Kieron Pollard was caught at deep midwicket to give Tahir five.
West Indies lost their last five wickets for 35 runs and were bowled out in 38 overs.