Ashwell Prince struck 98 to put South Africa in control of the second Test against West Indies on Friday.
At the close of the third day, West Indies were 96-4 in their second innings, a lead of just 18.
South Africa were dismissed for 321 in reply to West Indies' first innings' 243.
Prince batted for five hours, faced 225 balls and hit 11 fours in his patient innings.
Mark Boucher (59) and Prince steered the home side's charge with a 129-run stand for the sixth wicket.
Prince and Boucher resumed on 218-5, and they were separated after an hour when Boucher was bowled off the bottom edge of his bat by medium-pacer Dwayne Bravo.
Fast bowler Daren Powell dismissed Paul Harris (4) and Andre Nel (5) with catches by second slip Runako Morton and wicketkeeper Denesh Ramdin respectively as South Africa slipped to 284-8.
Prince was out in the third over after lunch when he tried to take a second run from a delivery by Powell and was caught short by Jerome Taylor's throw from third man to Ramdin.
"It would have been good to score a century but if I get 98 and we win the match I'll be happy," Prince told a news conference.
INJURED EDWARDS
Five overs later Dale Steyn (19) heaved a ball from leg-spinner Rawl Lewis down the throat of Morton at deep mid-wicket to end the innings.
Fast bowler Fidel Edwards did not bowl on Friday after leaving the field with an injured hamstring on Thursday.
Ramdin opened West Indies' second innings with Daren Ganga because captain Chris Gayle was receiving treatment for the hamstring injury he took into the match.
Ramdin, who batted at number seven in the first innings, scored 32 in a stand of 59 before edging a delivery from fast bowler Jacques Kallis to wicketkeeper Boucher.
Six balls later Morton (1) was dismissed in identical fashion by fast bowler Dale Steyn.
Ganga's 112-ball vigil for his 22 was ended when he dragged a delivery from fast bowler Makhaya Ntini onto his stumps.
West Indies slumped to 93-4 when fast bowler Andre Nel trapped Marlon Samuels in front for 18.
The visitors' chances of setting a challenging target would seem to rest with their overnight batsmen, the obdurate Shivnarine Chanderpaul (eight not out) and the aggressive Gayle (one not out), who came in at number six.
"They have two quality players at the crease and Dwayne Bravo to come," Prince added. "But if we take two quick wickets I think we'll be right in there."
West Indies lead the three-match series 1-0.
Scorecard
West Indies first innings 243 (Marlon Samuels 51, Shivnarine Chanderpaul 65 not out, Dale Steyn 4-60)
South Africa first innings 321 (Ashwell Prince 98, Mark Boucher 59, Dwayne Bravo 4-82)
West Indies second innings
D. Ganga b Ntini 22
D. Ramdin c Boucher b Kallis 32
R. Morton c Boucher b Steyn 1
M. Samuels lbw b Nel 18
S. Chanderpaul not out 8
C. Gayle not out 1
Extras (lb-14) 14
Total (for 4 wickets, 50 overs) 96
Fall of wickets: 1-59 2-60 3-81 4-93.
To bat: D. Bravo, R. Lewis, J. Taylor, D. Powell, F. Edwards.
Bowling: Nel 15-9-14-1, Ntini 14-8-25-1, Steyn 9-3-22-1, Kallis 11-4-19-1, Harris 1-0-2-0.
