Juan Martin del Potro came from a set down to beat Rafael Nadal in a pulsating semi-final and book a gold medal match against Andy Murray at Rio 2016.
In a breathtaking contest at the Rio Tennis Centre it was Argentine Del Potro that triumphed 5-7 6-4 7-6 (7-5) after more than three hours of sensational tennis.
Del Potro, bronze medallist in London four years ago, has slumped to 141 in the world after battling injuries for the past two years and he was brought to tears by his victory.
Nadal - who won the men's singles in Beijing eight years ago - himself was a fitness doubt before Rio and he fought valiantly having won gold in an epic doubles final on Friday, fighting back after losing serve in game nine of the decider.
But ultimately it was Del Potro that came out on top and he celebrated in exuberant style with the Argentina fans watching courtside.
Del Potro came out firing and when Nadal failed to put away a half-volley at the net the Argentine brought up break point with a clever lob and finished the job with a stinging forehand.
Nadal grew into the set and some stern defence coupled with going at Del Potro's backhand saw him break back for 3-3, and the Spaniard clinched the set when his opponent put a forehand into the net when trailing 6-5.
However, Nadal's standard dipped early in the second with too many first services failing to land, and a stinging Del Potro forehand down the line gave him a 2-1 break from which Nadal could not recover.
Both players saved break points in the early stages of the decider, but Del Potro earned three break points in game nine when Nadal went long with a lob attempt, and the Argentine took the second of those to earn the chance to serve for the match.
The drama was not done, though, and Nadal whipped the crowd into a frenzy when he brought up 0-40 and levelled the set again with a trademark fizzing forehand.
Nadal once again had to dig deep to fight back from 0-40 on his own serve and when Del Potro held at 6-5 down the match headed to a tie-break.
After taking a mini-break with the first point of the breaker, Del Potro failed to serve out on match point at 6-4 after another epic point, but Nadal put a forehand wide when serving to stay in it to bring an end to an epic tussle.