South Africa captain Graeme Smith admitted his players had been left "speechless" after pulling off a dramatic three-wicket win against World Cup co-hosts India.

The Group B clash in Nagpur was a game of mixed fortunes for both sides, as Sachin Tendulkar's 99th international century and Virender Sehwag's 73 got India off to a flyer batting first before Dale Steyn's five-wicket haul sparked a major collapse to 296 all out.

Half-centuries from Hashim Amla (61), Jacques Kallis (69) and AB de Villiers (52) raised hopes of a win but a fightback from India forced the Proteas to rely on final-over heroics from Robin Peterson (18 not out) to see them through with two balls to spare.

And the result - which takes them above England and up to third in the Group B table - could not have come at a better time for South Africa, who had thrown away what looked like an easy win in their previous game against the English.

"For 15 overs up front we took an absolute beating," Smith said.

"But for 75 we played some incredible cricket. Chasing 300 in the second innings was a hell of an effort from the guys and I think we're all pretty speechless.

"Winning and losing in the last two games, there's been some massive lessons for a lot of our guys. But the confidence that you get out of a win like this is huge."

He added: "Sachin and Viru [Sehwag] put us under massive pressure up front but the guys showed a lot of composure.

"We just needed to focus ourselves and keep hanging in there. When we got our chance we took it. It was some great bowling by Dale and some of the other guys chipped in.

"But to get over the line chasing is just a massive, massive thing."

Smith's counterpart Mahendra Singh Dhoni, meanwhile, felt the pressure of defending a total right down to the last over had taken its toll on paceman Ashish Nehra.

The left-armer was handed the ball instead of Harbhajan Singh, whose three for 53 had helped India gain a toe-hold in the middle overs.

"Bhajji [Harbhajan] was the only other choice for the last over," Dhoni said.

"But I thought it would be better to use the seamer. Maybe I was wrong, but I thought that was the better option.

"We just needed the bowlers to bowl in the right spot, but they were under tremendous pressure.

"The batsman played well, and if you're not bowling in the right spot more often than not you get hit."