Kumar Sangakkara, Sri Lanka's man of the match in Brisbane, said his team's recent poor performances in one-day internationals were no bad thing.
He said: "It's been a tough couple of months but it's done us a world of good. It shows you need a lot of character to play this game.
"You need to go through the tough times and keep yourselves together. Moments like these make it all worthwhile."
Sri Lanka's win over South Africa was only their third in 13 matches.
They easly triumphed over their opponents, who fell 94 runs short of their own score of 282-6 - despite having beaten Australia in a run chase at the weekend.
Sangakkara, who hit 88 with 10 boundaries, said: "The ball comes on at an even bounce here and there's not much movement so what more can you ask for as a batsman?"
But South Africa had elected to field first when winning the toss, giving Sri Lanka first use of the wicket and ensuring they would have to bat under floodlights - when conditions often begin to favour the bowlers.
Sangakkara went on: "Ever since the 1996 World Cup [which Sri Lanka won] we have had a great record in one-dayers.
"We owe a debt of gratitiude to those player and it's something we should be proud of.
"All the players should know their place in history and respect that."