West Indies will require another 227 runs from 44 overs to beat South Africa in the ICC Champions Trophy Pool B game here at the Oval on Sunday and go through to the semi-finals of the competition.
Saturday's play was suspended because of rain after South Africa had scored 246-for 6 from 50 overs.
The West Indies were 20 for 2 in reply from six overs when the weather interrupted for with Chris Gayle not out 12 and Wavell Hinds not out 6 as their side tried to book a semi-final date against either India or Pakistan.
For South Africa, Herschelle Gibbs hit 101 in 135 balls including nine fours and a six after South Africa were put into bat by Brian Lara.
Jacques Rudolph provided some clean-hitting making 46 from 39 balls with four fours and a six before he was bowled by the impressive Chris Gayle with four overs left and a steady fall of wickets stemmed the flow of runs.
Gayle was the pick of the West Indian bowlers taking 3-50 and Ian Bradshaw picked up 2-40.
Opener Gibbs has been in desperate run of form scoring just 93 runs in his last six one-day internationals and averaging a modest 20.8 in 32 games since the 2003 World Cup.
But coach Eric Simons resisted calls to drop the 30-year-old down the order and he responded with a well-paced innings that yielded his 13th one-day century.
He reached three figures with a straight six off Gayle but was out two balls later attempting to repeat the shot when Dwayne Bravo took a superb overhead catch at long-off.
With captain Graeme Smith, Gibbs put on 102 for the first wicket before Smith was bowled attempting to cut the gentle spin of Gayle in the 23rd over.
Apart from one uppish off-drive off Bradshaw, Smith had not been in trouble making 45 from 64 balls with five fours.
His dismissal brought in Jacques Kallis who played a subdued innings of 16 that was all made in singles until he was comprehensively bowled by Bravo.
Martin van Jaarsveld drove his first ball straight to Ricardo Powell when the final push was on and Mark Boucher (7) also perished chasing quick runs at the death.
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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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West Indies
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C. Gayle not out 12
W. Hinds not out 6
Extras: (1w, 1nb) 2
Total: (0 wkts, 6 overs) 20
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