The USA gave South Africa a scare in the first game of the World Cup Super Eights before succumbing to an 18-run defeat in Antigua.
With the South Africans set for a big boost to their net run-rate in a group also involving England and West Indies, they were pegged back by a blistering unbeaten 80 from 47 balls from the USA's South African-born batsman Andries Gous. Set 195, the Americans settled for a respectable 176 for six.
South Africa had arrived in Antigua after four low-scoring group games in New York and St Vincent, in which they didn't score more than 115. And while they had won all four, their were moments of jeopardy during victories by four wickets over the Netherlands, by four runs over Bangladesh, and by one run over Nepal.
Finally, on a good surface at the Sir Vivian Richards Stadium, they could free their arms. Opener Quinton de Kock blasted 74 off 40 balls and hit five of his team's 10 sixes, including three in the fourth over from seamer Jasdeep Singh.
Captain Aiden Markram contributed 46 off 32, before he became the second victim for left-arm seamer Saurabh Netravalkar, one of the stars of the tournament. But Heinrich Klaasen pummelled three late sixes to lift the South Africans to 194 for four.
Anrich Nortje of South Africa celebrates taking the wicket of Corey Anderson in Super 8 win
South-African born USA star Andries Gous reacts as he leaves the field during the game
Fans watch the Super Eight match between the USA and South Africa in Antigua
Steven Taylor gave the American chase a lively start before spooning Kagiso Rabada to mid-off for 24 off 14 balls, before a collapse left them 76 for five in the 12th over.
But Gous put on 91 in seven with Harmeet Singh, whose left-arm spin had earlier removed de Kock and David Miller with successive balls, and the USA needed 28 off 12 balls when Rabada's class closed the game down.
With South Africa, England and West Indies likely to battle it out for two semi-final spots, net run-rate could yet come into play - making each team's game against the USA an opportunity to massage their numbers.
England and West Indies were due to play each other in the small hours of Thursday morning in St Lucia, with England facing South Africa at the same venue on Friday.