Andy Murray never made it to this year’s Australian Open because of hip surgery, and 2014 champion Stan Wawrinka lasted only two rounds in his return from two knee surgeries in the second half of 2017. Novak Djokovic, the six-time Melbourne champion, fell to 58th-ranked Hyeon Chung in the fourth round, his serve reworked to take pressure off the problematic right elbow that ended his 2017 season in July.

Now Rafael Nadal has joined this parade of injury woe, retiring because of pain in his upper right leg in the fifth set of his Australian Open quarterfinal match against Marin Cilic on Tuesday.

“Tough moments — not [for] the first time here,” Nadal said, per the Associated Press. “I’m a positive person, but today is an opportunity lost to be in a semifinal for a Grand Slam and fight for an important title for me.

“It’s really tough to accept.”

Nadal’s departure against Cilic — officially scored 3-6, 6-3, 6-7 (7-5), 6-2, 2-0, retired — leaves only Roger Federer standing in Melbourne among the game’s most recent men’s greats (he faces Tomas Berdych, who ended his 2017 season in October because of back pain, in a quarterfinal Wednesday), a fact not lost on Nadal after he threw in the towel Tuesday.

“I wish Stan and Andy a good recovery, all the best for the future, healthy,” he told reporters. “Another thing is that there is too many injuries on the tour. I am not the one to say, but somebody have to look about what’s going on.”

A reporter asked Nadal whether he thought changes need to be made.

“I repeat: I am not the one to take decisions,” he said. “But when something is happening too often, something we are not doing well.”

The injury issue has roiled men’s tennis since last year, when none of the top 5 in the final 2016 rankings made it to the U.S. Open and Federer, Berdych, Djokovic, Murray and Wawrinka all withdrew from the season-ending Paris Masters along with Nick Kyrgios, Kei Nishikori and Milos Raonic.

“To me it doesn’t set off a red light; it sets off a yellow light,” Paul Annacone, a former pro who later coached Pete Sampras, Tim Henman and Federer, told the New York Times last year. “Let’s see if it continues. I think it’s been one of those years, but if it goes into 2018, then I would start to go: What is happening? What are we doing? Is it the physicality? The heaviness of the balls? The length of the season?”

The ATP has instituted changes to reduce wear and tear on the tour’s veterans over the 11-month schedule, giving exemptions from its mandatory Masters 1000 events for anyone who has been on tour for 12 years, played 600 matches or is 31 or older. If a player meets all three of those benchmarks, he can skip all the Masters events he wants. But thanks to Nadal’s injury and his reaction to it, the issue already has reared its head barely one week into the first Grand Slam of the season.

It’s impossible to talk about any of this without noting that the most prominent players in the men’s game all are getting along in years (at least in comparative terms). Djokovic and Murray both are 30 (they were born within a week of each other in May 1987). Wawrinka is 32. Federer is 36. Nadal is 31, has been playing professionally since he was 15 and has battled injuries throughout his career thanks in part to his punishing style of play: a foot injury that kept him out of the season-ending Masters tournament in 2005 and the Australian Open in 2006, a knee injury suffered during the 2007 Wimbledon final, knee tendinitis that affected him in 2008 and kept him out of Wimbledon in 2009, hamstring and foot injuries in 2011, back and wrist injuries in 2014, and a wrist injury that forced an early withdrawal from the 2016 French Open and a complete withdrawal from Wimbledon.

That’s simply an excessive amount of wear and tear, and at some point we have to consider whether Nadal’s most recent injury is the result of overlong seasons or a standout career that has stretched on past any reasonable expectation.

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