Zverev fought back from a set and a break down to pull off a staggering 1-6 6-3 6-1 win over the Serbian world number one to set up a final showdown with Karen Khachanov of the Russian Olympic Committee.

Fifth-ranked Zverev is the first German man to make an Olympic final since Tommy Haas won silver at the Sydney Games in 2000.

Djokovic had arrived in Tokyo gunning for the Golden Slam — winning all four majors and Olympic gold in the same year — after triumphing at the Australian Open, Roland Garros and Wimbledon in 2021. The U.S. Open begins next month.

Victory in Tokyo would also have secured the 34-year-old Djokovic the only major honour still missing from his collection — an Olympic gold medal

But the 2008 Beijing Games bronze medallist lost that chance after Zverev secured the win with a crushing backhand down the line winner.

As an emotional Zverev embraced his opponent at the net, he told Djokovic “I’m sorry”.

“I told him that he’s the greatest of all time,” Zverev later told reporters.

“But in these kind of moments, we’re very close and we’re good with each other, so of course, I’m happy that I won but at the end of the day I also know how he feels.”

The 24-year-old said he changed his tactics to avoid getting flattened after the Serbian, who had lost only three matches in 2021 before arriving in Tokyo, took the first set and went up a break midway through the second.

“I didn’t feel I was playing that bad, but I was playing his game kinda, in a way,” said Zverev, who had lost his last five meetings against Djokovic dating back to 2018.

“I was rallying with him a lot and I needed to swing through the ball a little bit more and to step up a little bit more and yeah, it worked out well.”

Earlier on Friday, 25th-ranked Khachanov outgunned Spain’s Pablo Carreno Busta 6-3 6-3 with his trademark power-hitting.

Khachanov, who made the Wimbledon quarter-finals earlier this month, described the match as a highlight of a memorable summer.

“I play tennis for those moments, I practise for these kind of matches and when you get there, when it’s paying off, it’s just a pure pleasure to be here…,” he said.

“(It’s) the kind of memories that will stay forever.”

In the men’s doubles, Marcus Daniell and Michael Venus handed New Zealand their first Olympic tennis medal when they claimed bronze following a 7-6(3) 6-2 win over Americans Tennys Sandgren and Austin Krajicek.

Marin Cilic and Ivan Dodig will play compatriots Nikola Mektic and Mate Pavic for the gold medal in an all-Croatian final later on Friday. (Reporting by Rozanna Latiff; editing by John Stonestreet and Pritha Sarkar)