Belinda Bencic became the first Swiss woman to win Olympic tennis gold as a racquet-smashing Novak Djokovic left Tokyo without a medal.
Bencic beat Czech Marketa Vondrousova 7-5 2-6 6-3 in the singles, and could still add another gold in the doubles.
Earlier, a frustrated Djokovic lost to Pablo Carreno Busta in the men's singles as the Spaniard took bronze.
The Serb later withdrew from the mixed doubles bronze match because of a shoulder injury.
"I gave it all, whatever I had left in the tank, which was not so much. I felt it out on the court," said Djokovic, who threw one racquet and smashed another in a 6-4 6-7 (6-8) 6-3 loss to Carreno Busta.