Novak Djokovic came clean, or so it seemed, right after his third-round victory at the Australian Open, about pain in his midsection after an awkward, torso-twisting slip.

Asked that night about being ready for his next match, Djokovic replied: “I know it’s a tear, definitely, of the muscle. ... I don’t know if I’m going to step out onto the court or not.”

Narrator: He did. And not only was the 17-time major champion back in Rod Laver Arena two days later — he played well enough with that bothersome and bandaged abdominal to reach the quarterfinals. This time, when reporters inquired, Djokovic clammed up.

“I know what it is," said Djokovic, who plays Alexander Zverev on Tuesday, “but I don’t want to talk about it now.”

Unlike in certain team sports — think of the NFL’s “doubtful” or “questionable” designations accompanied by listings of specific body parts in a nod to gamblers, rather than the “upper body” or “lower body” vagueness often used in the NHL — Grand Slam tennis leaves it up to individual players to decide whether to disclose or discuss injuries before they compete.

Some are more forthcoming than others. Some go back and forth.

“Depends what you have,” 2019 U.S. Open finalist Daniil Medvedev said.

It's a big deal in a sport where fitness is key and it's not unusual to see players stop mid-match or not show up at all because of injuries. There was one example of each Monday, when Casper Ruud retired after the second set against Andrey Rublev, and Matteo Berrettini gave Stefanos Tsitsipas a walkover.

While players and coaches are not required to reveal anything to the media, Grand Slam rules dictate that anyone withdrawing before a singles match, or quitting during one, must be seen by a tournament doctor.

That way, whatever reason was cited can be verified before prize money is paid.

There are those who play it coy, lest an upcoming foe glean some sort of competitive advantage. And there are those who insist they wouldn't do that.

“It’s difficult to hide things,” said Rafael Nadal, who had to reveal he was dealing with a bad back when he pulled out of another event recently. “I mean, even if you want to hide, at some point you’re going to have questions to answer. I don’t want to play that game, honestly.”

Perhaps. But during the 2016 French Open, Nadal kept a bad left wrist secret until he suddenly showed up with a blue brace for a news conference and announced he was out of the tournament.

Serena Williams made surprise exits from Roland Garros before matches in 2018 (pectoral muscle) and last year (Achilles tendon), citing injuries she had avoided discussing. On Sunday at the Australian Open, she casually made a passing reference to the Achilles having “been a problem since 2018,” which was news to most everyone.

Nadal and Williams are among the players who tend to avoid blaming defeat on injury, lest they sound like someone withholding credit from the winner.

When reigning U.S. Open champion Dominic Thiem appeared to be hampered during a straight-set setback against Grigor Dimitrov in Melbourne, he chalked it up to a combination of having “some little physical issues, plus a real bad day, plus the fact that, well, he’s a great player,” but never offered any specifics.

Williams’ coach, Patrick Mouratoglou, would rather just hear what really was going on.

“A lot of players, after losing, they want to look gracious, so they say, ‘Oh, no, I’m fine.’ They’re clearly not fine,” Mouratoglou said. “It’s just to look good."

After Victoria Azarenka appeared to have difficulty breathing during a loss to American Jessica Pegula last week, the two-time Australian Open champion objected to a reporter’s question about whether she was sick.

“I don’t really know why we’re getting asked about some, like, medical conditions (of) players, because all this is going out on the internet after, for people to talk about, to judge about,” Azarenka said. “It shouldn’t be a mandatory requirement for people to talk about their health issues.”

It’s not, of course, but Djokovic agreed with her general premise, saying he doesn’t “feel comfortable” talking about such matters.

Then again, he was the one who fueled the conversation about his status in Australia by telling the world he had a torn muscle.

Back in 2008, during the U.S. Open, Andy Roddick teased upcoming opponent Djokovic for seeking a trainer’s help for hip, ankle, stomach and breathing problems during another match.

Joking about whether Djokovic’s list of laments also included bird flu, anthrax, SARS and a common cold, Roddick concluded: “He’s either quick to call a trainer or he’s the most courageous guy of all time.”

In the end, though, Djokovic got the last laugh: He beat Roddick by a healthy margin, 6-2, 6-3, 3-6, 7-6 (5).

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