Few would have placed their bets on Juan Martin del Potro at the Rio Olympics, but the Argentinian has clinched the chance to win gold in Sunday's tennis final against 2012 champion Andy Murray.
In Saturday's semi-final, the world's 141st-ranked player delivered a gripping fight against Spanish star Rafael Nadal over 3 hours and 8 minutes that ended 5-7, 6-4, 7-6 (7-5)
The Argentinian already led 3-1 in the first set and ended up losing it. But he kept his nerve.
In the third set, he was poised to decide the game at 5:4, but the battle went on after his service was broken to love.
After being unable to take three break points, del Potro was forced into the tie break and ended up profiting from a final error by Nadal in the second match point.
Del Potro, who had been out for wrist surgery for nearly a year until February, was filled with emotion and kissed the court, before getting embraced by throngs of ecstatic Argentinian fans. The triumph Saturday follows on that in the first round of the tournament when he ousted top-seeded Novak Djokovic of Serbia.
Amid all del Potro's post-match celebrations, it took awhile for it to sink in what he had accomplished.
"I'm just beginning to understand that I've won a medal," the Argentinian said.
Wimbledon champion Andy Murray meanwhile secured his chance of back-to-back Olympic golds by beating Japan's Kei Nishikori 6:1, 6:4 his semi match earlier on Saturday.
Murray thrashed the fourth-seeded Japanese player in under half an hour in the first set, dropping just one game in the process.
In the final game of the second set, the pair brought the Rio crowd to its feet with a rousing rally, which Murray won to set up match point.
The Scot then sealed the match with a powerful second serve that Nishikori was unable to return.
Murray won gold in London in 2012 and would be the first tennis player ever to retain the Olympic title should he win on Sunday.
"Juan Martin has played great this event, getting a lot of confidence from his win against Novak," Murray said.
"He won against (Stan) Wawrinka at Wimbledon, so he's getting back to that level he can play at. After his wrist problem that's good for him," Murray said.