MELBOURNE, Australia — After missing the game he has long played with such passion, Rafael Nadal has had ample opportunity to get reacquainted with tennis at this Australian Open.

At age 35, his latest comeback from injury now finds him in the semifinals, just two victories from breaking his three-way tie with Novak Djokovic and Roger Federer and claiming his 21st Grand Slam singles title.

But it also briefly found him on the defensive Tuesday after his opponent, Canada’s Denis Shapovalov, said Nadal had benefited from favoritism in their quarterfinal, which Nadal won by taking command of the fifth set to prevail, 6-3, 6-4, 4-6, 3-6, 6-3, in four hours and eight minutes.

Shapovalov did not take the defeat well, smashing his racket to the blue hardcourt in Rod Laver Arena immediately after his final volley drifted wide. It was a stark contrast with Nadal, who has never broken (or thrown) a racket in anger during a match in his nearly 20-year professional career.

But Shapovalov was both crestfallen and disappointed with Nadal, the Spanish champion whom Shapovalov first met as a nine-year-old ball boy during the Canadian Open in Montreal and then defeated, Hollywood-style, in the same city in their first match in 2017.

However wide-eyed Shapovalov might once have been about the Spaniard, though, he did not hold back on Tuesday: complaining during and after the match that Nadal was being allowed more time between points than permitted.

After winning the first set, Nadal changed his clothes and was slow to leave his chair after the umpire, Carlos Bernardes, called “Time.” Shapovalov took the balls and prepared to serve as he waited, and when Nadal finally made it on court, Shapovalov approached Bernardes and said Nadal should have been penalized for the delay.

Shapovalov later repeated, “You guys are all corrupt,” to Bernardes before serving.

Shapovalov, 22, received no code violation for the comment and later said, apologetically, “I think I misspoke.” But he also complained during the match that Nadal was stretching the spirit of the rules by taking an extended break before the final set for a combined medical timeout and toilet trip.

Shapovalov quizzed Bernardes at length as they awaited Nadal’s return, saying that he had not been allowed to combine the two at a past tournament. Shapovalov repeated his accusations of favoritism in a news conference after his defeat.

“They are legends of the game,” he said of stars like Nadal, “but when you step on the court it should be equal.”

Bernardes, a veteran chair umpire from Brazil, did give Nadal a time violation for taking too long before serving in the fourth set. Bernardes and Nadal have not always been in agreement, and Bernardes was kept from working Nadal’s matches during a cooling-off period in 2015. But that informal ban soon ended.

Nadal rejected Shapovalov’s accusations of favoritism and said it was standard practice to take a bit more time to change clothes and equipment after a set played in such steamy conditions.

“I think he really was wrong,” Nadal said in Spanish of Shapovalov. “When you lose a match like this, you are frustrated. I have a lot of affection for Denis. I think he’s a good guy with lots of talent, the talent to win multiple Grand Slams. In no way do I want to get in an argument with him. But I think he’s wrong. He’s young and when one is young, one makes mistakes.”

Nadal observed that the rules had been tightened in recent seasons to make it harder to show favoritism to the elite or any player because of the advent of electronic line-calling, shot clocks between points and, this season, stricter time limits on toilet breaks.

“You have less room now to influence anything,” said Nadal, who added that he was not interested in getting an advantage on court.