The 24-year-old saved five set points in a 73-minute opening set before winning 7-6 (7/2), 4-6, 6-3 after almost two-and-three-quarter hours in the searing Tokyo heat.

Bencic, who plays alongside Viktorija Golubic later Thursday in the women's doubles semi-finals against Brazilian pair Laura Pigossi and Luisa Stefani, will face either Elina Svitolina or Marketa Vondrousova in the singles final.

The ninth seed is bidding to become the fifth player to reach finals in both singles and doubles at a summer Games since tennis was reintroduced to the Olympics in 1988.

Thursday's programme began at 3:00 pm (0600 GMT) local time, after organisers pushed the start time back from 11:00 am following complaints from players about the hot conditions.