Argentina's Juan Martin del Potro has booked himself a spot in the Olympic tennis men's singles final after overcoming Spain's Rafael Nadal in a topsy-turvy clash at the Rio Games.
The 27-year-old, who won a bronze four years ago in London, will add a silver or gold to his collection following his comeback to stun the third seed 5-7 6-4 7-6(5) on Saturday.
Nadal, who won gold in the men's doubles with Marc Lopez on Friday, took the first set before Del Potro levelled.
Both men played emphatically in the decider, with Nadal breaking back at 5-4 down, but it was eventually in vain as his opponent won the decider 7-5 in the tie-break.
Del Potro will play current Olympic champion Andy Murray of Great Britain on Sunday.