Novak Djokovic maintained his Golden Slam bid by thumping Japanese hope Kei Nishikori to reach the men’s Olympic tennis semi-finals, while his chief gold-medal rival Daniil Medvedev was dumped out on Thursday.

In the women’s draw, Switzerland’s Belinda Bencic set up a final against Naomi Osaka’s conqueror Marketa Vondrousova with a marathon victory over Kazakh Elena Rybakina.

World No 1 Djokovic, who has already sealed the Australian Open, French Open and Wimbledon titles this season, brushed aside Nishikori 6-2, 6-0 in just 70 minutes.

“My best performance of the tournament tonight against the very good, very good opponent,” said Djokovic, who is looking to emulate Steffi Graf’s 1988 Golden Slam – winning all four Majors and the Olympic singles in the same year. “I feel I had an answer for everything he had.”

The Serb did not have to be in peak form against an opponent who offered very little and made 16 unforced errors.

The 34-year-old Djokovic, whose best Olympic result was a bronze medal in Beijing 13 years ago, will face German Alexander Zverev in the last four on Friday after the fourth seed’s 6-4, 6-1 win over Jeremy Chardy.

Djokovic looked comfortable throughout against Nishikori, with the match played in cooler conditions than earlier rounds after he and Medvedev were among players to lobby organisers to change the schedule. The day’s start time was pushed back from 11:00 am local time (0200 GMT) to 3:00 pm.

“It’s great that we’re playing in the afternoon hours, so we don’t experience too much heat, although it’s still very, very humid,” he added.

Djokovic will now be the hot favourite to reach the final for the first time.

He holds a 6-2 winning record over Zverev and has beaten the world number five in their last five meetings.

‘I wanted to change my skin’

The top seed could still win two golds in Tokyo, with his mixed doubles quarter-final alongside Nina Stojanovic, against Germany’s Kevin Krawietz and Laura Siegemund, to come later on Thursday.

Djokovic’s path to singles glory was made easier when second seed Medvedev was dumped out by Pablo Carreno Busta.

Spaniard Carreno Busta, on his Olympic debut, set up a semi-final with another Russian, Karen Khachanov, by beating an out-of-sorts Medvedev 6-2, 7-6 (7/5).

Medvedev, a two-time Grand Slam finalist, made 26 unforced errors as he struggled to find his usual rhythm, smashing his racquet in frustration at the end of the match before again complaining about the heat.

“I wanted to change my skin because I was sweating like I never did before. It was terrible,” he said.

Khachanov had earlier battled past France’s Ugo Humbert 7-6 (7/4), 4-6, 6-3.

Earlier ninth seed Bencic had to dig deep to edge out Rybakina after playing for two hours and 44 minutes in the searing heat first up on centre court. She saved five set points in the opening set before winning 7-6 (7/2), 4-6, 6-3.

Vondrousova, the 2019 French Open runner-up, stands in her way on Saturday after again impressing against a high seed by thrashing Elina Svitolina 6-3, 6-1.

“I don’t feel pressure right now. I just feel joy to have a medal,” said an emotional Bencic.

Czech left-hander Vondrousova, ranked 42nd, won the pair’s only previous meeting earlier this year in Miami.

The men’s doubles final will be only the third Olympic final between the same country – with Marin Cilic and Ivan Dodig to play Nikola Mektic and Mate Pavic on Friday.

Women’s world number one Ashleigh Barty kept her golden dream alive despite defeats in the singles and women’s doubles, reaching the mixed doubles semi-finals with John Peers after victory over Greek stars Maria Sakkari and Stefanos Tsitsipas.