Nadal's Olympic warning as Norrie is put to the sword

The 38-year-old, who opted to miss Wimbledon in order to focus efforts on the Games, had his serve broken by fifth-seed Norrie, who was looking to level the match after going down 6-4 in the first set. 

But having received treatment on court to his arm after talking a heavy fall, Nadal came back to claim a 6-4 win in the set and progress to the quarter-final where he will face Argentinian Mariono Navone. 

"Great feelings, it's been a while without playing on the Tour since Roland Garros and I had a chance to compete against a great player like Cameron," said Nadal. 

"It's part of the journey today. I haven't been competing very often so matches like today help and holding the pressure on the opponent for the whole game is something I need to improve on because I haven't played enough." 

Nadal, who will play singles and doubles with Carlos Alcaraz in Paris, where he became a record 14-times French Open winner, broke Norrie once in the first set to set up what at the stage looked like being a routine win.

But having fallen behind in the second set, he required a five-game winning run in order to edge through. 

In Hamburg, defending champion Alexander Zverev defeated Frenchman Hugo Gaston 4-6 6-2 7-5 to secure his spot in the quarter-finals of the Hamburg Open.

Zverev initially struggled and lost the first set after 47 minutes.

He contested a point when he thought the ball had double-bounced in Gaston's court.

"I was on the verge of losing my nerve completely once or twice. You stopped me from doing that," the Hamburg native said after the match, thanking the home crowd for their support.

Zverev managed to rally and win the second set.

In the third set, there was some debate when Zverev initially thought Gaston's ace was out, but the chair umpire ruled it as good. Zverev later received a warning for taking too long during a serve.

Despite losing two service games in the third set, Zverev managed to win the match 6-5 after 2 hours and 35 minutes, finishing with an ace at the first match point.

Zverev defended the umpire, stating people were allowed to make mistakes.

"Everybody has bad days," he said.

However, he called for the introduction of video review technology.

"The bigger question is we have the technology to review these kinds of things," he said.

"Not sure why we're not using it on Tour yet. These kinds of situations, these kinds of things can cost the player the match, it cost me the set today which was very unfortunate."

Zverev will meet China's Zhang Zhizhen in the next round on Friday.

with DPA