And the second quarterfinal began molasses-slow when No. 3 Carlos Alcaraz and No. 12 Tommy Paul played a first set that lasted 1 hour 12 minutes. Alcaraz picked things up after that and defeated the American, 5-7, 6-4, 6-2, 6-2, to set up a rematch of last year’s semifinal against Medvedev.

But even Alcaraz, who is in the hunt to back up his French Open title with his second Wimbledon championship in as many years, couldn’t escape a marathon match this fortnight. His third-round battle with Frances Tiafoe went five sets and took 3 hours 50 minutes.

Medvedev’s theory? That’s just grass-court tennis, with its quick points and games dictated heavily by the quality of your serve.

“Maybe the level is closer than before,” he said Tuesday — and that’s a strong possibility, too, with Novak Djokovic the outlier of the bunch with his 24 Grand Slam titles and everyone else knotted together just a hair behind that.

“In my opinion,” Medvedev continued, “grass is always a surface where it’s very tough to win straight three sets, like [6-4, 6-4, 6-4]. One break can decide the outcome of the set.”

And then there is the weather.

Rain has drenched the All England Club over the first nine days of the tournament, falling in just about every variation imaginable — along with a momentary bout of hail Sunday — and coming almost daily. Only two days have been completely dry so far.

That has affected attendance: The first week of the tournament drew 293,681 visitors in 2023 but just 282,955 hearty souls this year. But it also has altered the rhythm of matches played on the outer courts. Player after player has had a match delayed and interrupted mid-set, which tends to lay the groundwork for a change of momentum.

No. 14 Ben Shelton, who lost to Sinner in the fourth round Sunday, felt that when he played three five-set slugfests in his first three matches. His third-round match against Denis Shapovalov was suspended because of rain with Shapovalov leading 3-2 in the opening set. The American had a full night to think about adjustments — and Shapovalov had time to counter.

“Shapo started doing a really good job in the fourth set of returning my serve, finding a way to neutralize, so I had to change it up. In the fifth set, I served almost every serve into the body and serve-and-volleyed,” Shelton said. “I think that’s the part that I like the most about it — the game within the game.”

Shelton’s appreciation of five-set tennis is a popular opinion among players and fans alike, who consider the men playing best-of-five matches at Grand Slams — as opposed to best-of-three, which the men play at non-Grand Slams and the women play all the time — a special mental and physical demand that separates the pretenders from the greats and elevates the majors.

Some argue five-set matches inherently mean high-quality drama. But the momentum swings that lead to five sets are frequently just that — undulations that aren’t any more epic than what unfolds in a three-set match. They just last longer.

Medvedev and Sinner rode that roller coaster Tuesday even before the top-ranked Italian felt so ill and dizzy that he left the court for a medical timeout in the third set. He returned, briefly rejuvenated, to win the fourth before an ultra-aggressive Medvedev closed the match to gain a modicum of vengeance against Sinner after surrendering a two-sets-to-none lead to lose the Australian Open final.

“For me, this is tennis at its pure sport, pure game,” Medvedev said, going on to describe the opportunities Sinner had to win the third set Tuesday and the opportunities he had but couldn’t grasp to win in Melbourne. “That’s why people love tennis. That’s why people get crazy watching tennis. That’s why we tennis players sometimes get crazy playing tennis.”

Crazy, sometimes. Tired? Almost always in a marathon match. Five-setters offer unforgettable moments just as often as they devolve into battles of attrition that suck up hours of airtime and sour viewers. That’s why the 37-year-old Djokovic, who has yet to have a match go the distance at this Wimbledon, has a compromise that could suit players and time-conscious fans: He suggested men’s matches go to best-of-five only in the later rounds of Grand Slams.

“That’s just me, my thinking. I think best-of-five, particularly in the last three or four rounds of a Slam, you need to keep,” said the second-seeded Djokovic, who faces No. 9 Alex de Minaur in a quarterfinal Wednesday. “But in terms of innovation in tennis, in our sport, I think it’s necessary. I think we have to, other than Slams, figure out how to attract young audience.”