Federer wasn't going to do that when he played Grigor Dimitrov on Tuesday, of course. But he could have. Without any punishment. That's because, as Federer himself noted during an interview with The Associated Press this season, players are not required to take part in the five-minute pre-match warmup seen at every professional tennis tournament, Grand Slam or otherwise.
"I could just walk in and say, 'I'm OK. I'm ready.' And then the other guy has ... to scramble and try to find somebody to warm up with on that court," Federer said with a mischievous smile, his eyes wide and eyebrows raised. "Imagine that. What a scene! It would be so weird. That doesn't happen; it's like a gentleman's agreement that you just do it."
He is right, of course: That preparation period is not mandatory. "There's nothing in the rules," explained the U.S. Open's chief umpire, Jake Garner, "that says you have to do it." He confirmed everything else Federer said, too, including that if one player declines to join in, the other is allowed to hand a racket to pretty much anyone he or she wanted as a replacement. Doesn't even have to be a coach or regular hitting partner, because nothing's been written down to account for exactly how to handle that situation.
"If this started to be an issue, we would legislate," said Gayle David Bradshaw, executive vice president for rules and competition at the ATP men's tour. For now, even if not codified, the five-minute warmup is as much a part of what happens before a match at Flushing Meadows — or anywhere else, really — as the coin toss or the player introductions.
It follows a familiar script. Groundstrokes exchanged from the baselines; one player, then the other, moves closer to the net and gets fed balls for volleys, then overheads; both players practice serves and, sometimes, returns.
In sum, foes help each other get ready to try to beat each other right before play begins, an unusual sight at the highest levels of sports. "I know it's not required," 2017 U.S. Open runner-up Madison Keys said, "but I can't imagine anyone deciding not to do it."
Federer made the point that the whole thing is somewhat superfluous, anyway, because players always go to a practice court to work up a sweat before heading to their match court. It's not as if they need to loosen up again immediately before competing.
"I feel," Federer said, "like we could get rid of that entirely." That's what the NCAA did for college tennis matches. "How about just playing?" he suggested, "A big announcement in the stadium: 'Roger's coming in.' 'This guy's coming in.' 'Please welcome So-and-So.' But then the match starts right away."
Garner, who worked 18 Grand Slam finals as a chair umpire, couldn't recall an instance of a player refusing to warm up before a match he was overseeing. It does happen occasionally, though. Two examples in recent years involved matches that followed lengthy rain delays, which allow players to ask for 10 minutes, instead of the usual five, to warm up before action starts.
Marcos Baghdatis, the 2006 Australian Open runner-up who retired last month, described a dispute at the Qatar Open in late December with Lukas Rosol, a former top-30 player best known for upsetting Rafael Nadal at Wimbledon in 2012.
"I asked the referee, 'Can we get a 10-minute warmup?' And Rosol says, 'No, I warmed up on the wet courts.' I said, 'Yes, but I didn't,'" Baghdatis recounted. "And then what I told him was: 'OK, there is another rule, that I am not obliged to warm up with my opponent.' So I told him, 'OK, I don't want to warm up with you. I want to warm up with my coach for five minutes. So you go find a person to warm up with.'
"And then he told me, 'No, let's do it for seven minutes.' Yes, for seven minutes!" Baghdatis said with a laugh. "We negotiated!" Sascha Bajin, who has worked with Serena Williams and Naomi Osaka and now coaches Kristina Mladenovic, recalled that at a tournament in Japan in 2017, the player he was with at the time, Caroline Wozniacki, brought him out of the stands to hit on court after her opponent refused a warmup following a rain delay.
"Caroline was looking at me from the sideline, and she was like, 'Yo, can you jump in?' and I was like, 'What?!' Full crowd. Live on TV," Bajin said. "And I jumped in and I warmed her up for five minutes on court. I was a little nervous."
Unlike Federer, Bajin wants the warmup to remain a fixture. "I do believe it's essential. A lot of fans maybe don't even know, but the outside courts, especially hard courts, play different. They are faster outside most of the time than they are on the big stadiums, because they get used more," he said. "So they can play completely different and it just makes it fair for everybody to warm up where they are playing."
Chris Evert, an 18-time major champion, agrees. For one thing, she said, while stars such as Federer, Nadal, Novak Djokovic or Serena Williams get to play in Arthur Ashe Stadium and other tournaments' main venues regularly, those places are unfamiliar to most others on tour.
"I'm a traditionalist and I think that for me, as a player, I'd always want to go out there and hit a few balls. For five minutes, they can go, move around the court, assess their opponent," Evert said. "What happens if they've never played on center court before? You want to warm up there. You want to see how fast the surface is. You want to practice serves."
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