West Indies captain Brian Lara praised his side's composure and discipline after they had successfully chased 247 to beat South Africa here at the Oval and win a place in the ICC Champions Trophy semi-finals next week.
The West Indies reply was interrupted by Saturday's rain and they resumed on 20 for no wicket. They passed their target with seven balls to spare and now look forward to the semi-finals - against Pakistan or India.
Despite being behind the required run-rate for most of their innings the West Indies always had wickets in hand and a late onslaught from Ricardo Powell, who scored 16 from ten balls sealed the game.
"We won the crucial parts of the game," said Lara.
"On Saturday South Africa were 105 in 21 overs without losing wickets and I thought they were going to get 275 but Ryan Hinds came in and bowled ten overs for 35 which was very important.
"We lost two wickets but I was not worried about the run-rate. Lance Klusener and Nicky Boje were bowling well but then Shivnarine Chanderpaul and Ricardo Powell came in and finished it in style.
"Having wickets in hand is what one-day cricket is all about and we knew we had guys like that in the shed to do the job so I was not worried about the situation. If we had lost a couple of quick wickets it would have got a bit dicey but we didn't."
For South Africa this was an 11th one-day defeat in 12 matches and captain Graeme Smith blamed his side's lack of runs in the middle overs of their innings for their failure to set a bigger target.
"If we have to be critical of the batting then we did not score enough runs between the 20th and 40th overs when we only scored 70-odd in 20 overs and 260 is a very different score to 245," said Smith.
"We have not played at our best for the last nine weeks and we are very disappointed. We go back to provincial cricket now and that gives us some time to think about where we are and where we need to go."
Man of the match Ramnaresh Sarwan (75), Lara (49) and Chanderpaul (51 not out) were the main contributors to the run chase but Powell's knock tilted the match towards the West Indies.
Powell came in at 214-4 with four overs left but turned the contest with two successive sixes off Shaun Pollock - full-tosses that he planted into the stands over mid-wicket.
Lara had stressed the importance of keeping wickets in hand on Saturday night but openers Chris Gayle and Wavell Hinds were soon back in the pavilion.
Thereafter the West Indies followed his instructions almost to the letter. Gayle attempted a pull from the last ball of the first over of the day from Pollock but edged the ball onto his stumps and Hinds was undone leg before by the former South African captain's next delivery.
Lara came in on 33-2 and survived the hat-trick ball pushing it to short mid-wicket before setting off for a run only for Pollock's attempted shy at the stumps narrowly miss with the batsman well short of his ground.
Lara and Sarwan adopted a studious approach as Klusener bowled an impressively tight spell of 0-32 from ten overs whilst Jacques Kallis went for just 14 from four overs.
Once Lara had gone the onus fell on Sarwan and Chanderpaul to up the scoring rate.
The Guyanese pair did this impressively with the fourth 50 of the West Indian innings coming up in 37 balls.
When Sarwan was bowled by Makhaya Ntini with 33 runs still needed for victory the game was in the balance but Powell's fireworks ensured the West Indies got home.
SCOREBOARD
SOUTH AFRICA
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G. Smith b Gayle 45
H. Gibbs c Bravo b Gayle 101
J. Kallis b Bravo 16
J. Rudolph b Gayle 46
M. van Jaarsveld c Powell b Bradshaw 0
S. Pollock not out 12
M. Boucher c Chanderpaul b Bradshaw 7
L. Klusener not out 13
Extras: (4lb, 2w) 6
Total: (6 wickets, 50 overs) 246
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C. Gayle b Pollock 16
W. Hinds lbw Pollock 15
R. Sarwan b Ntini 75
B. Lara b Boje 49
S. Chanderpaul not out 51
R. Powell b Ntini 16
D. Bravo not out 4
Extras: (10lb, 8w, 5nb) 23
Total: (5 wkts,48.5overs) 249
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