Bridgetown - Proteas captain Graeme Smith fell just before lunch to bring West Indies back into the third and final Test on Sunday.
Smith fell for 70, after putting on 62 with Jacques Kallis for the fourth wicket, as the South Africans, replying to West Indies' first innings total of 231, reached 145 for four at the interval on the second day at Kensington Oval.
Smith was unflappable throughout his 159-minute stay at the crease, and reached his 50 from 79 balls, when he worked Shane Shillingford through backward square leg for two.
He survived an umpiring decision review for lbw to Sulieman Benn, when he was 60, and had his sights set on his second hundred of the series.
But Smith misread his 115th delivery from Benn in the final half-hour before the interval, played defensively forward, and gave a bat-pad catch to forward short leg. He struck nine boundaries in his innings.
Smith and Kallis had cooled West Indies' passions, after Brandon Bess claimed his maiden Test scalp, when night-watchman Paul Harris was caught at first slip for 11 in the first half-hour of a sun-kissed morning.
South Africa lead the three-Test series 1-0, after they won the first Test by 163 runs inside four days last Sunday at Queen's Park Oval in Trinidad, and the second Test was drawn at Warner Park in St. Kitts.