Maria Sharapova, the fighter that she is, almost never cracks so much as a smile on court once the chair umpire begins play.
Almost never, because as she began her campaign with a victory over Agnieszka Radwanska on Sunday night, the microphone clipped to her coach could perhaps have picked up the merest hint of a chuckle from the world No. 4 during a changeover.
Sven Groeneveld, coach to the Russian since the end of 2013, suddenly seemed to resemble a novelist in her eyes.
"He pulled out a Paulo Coelho quote or something," she said, referring to the Brazilian author.
"(It was) 'Stop with the frustration, and go with determination.' I was like, all right buddy, slow down. I usually don't laugh in those moments, but that was a moment where I was like, okay, Sven."
It may be hard to quantify exactly how useful that brief piece of advice was - she rallied to beat Radwanska in three sets that night - but Sharapova is not opposed to a little pep talk.
She said: "I think I would like it if it didn't exist, and like it when it exists. It's there. If you have the chance to use it and you feel you need a few words to get you going or keep you focused, nothing is going to change drastically."
On-court coaching, now into its seventh year on the WTA Tour, is clearly not done for novelty value. Now, players even have access to real-time performance data during matches, an initiative introduced just two months ago at the Bank of the West Classic in Stanford.
But whether or not a coach should be allowed onto the court in a sport steeped in tradition remains a highly divisive topic.
"Tennis is a very individual sport," former world No. 1 Arantxa Sanchez-Vicario told The Straits Times. "It's not that I'm against it or for it... (and) I know it helps players sometimes, but at the end it's the player who has to win the match."
Marion Bartoli, who retired after winning Wimbledon in 2013, wishes she had access to the live analytics before she quit the sport.
She said: "The human eye is one thing but when it's on a computer it takes away all the emotions and it's so much clearer."
"You can literally isolate completely one shot, one pattern or tactic a player is using against you," added the Frenchwoman. She would especially have liked to use the information to formulate a solution against Radwanska, the Pole whom she never defeated in seven meetings.
But Bartoli would stop at allowing a coach on the bench throughout the match, saying that would be "too much".
Her countrywoman, Mary Pierce, however, is all for it. Said the two-time Grand Slam champion: "When you really think about it, what other professional sport does not allow coaching?
"When you see other sports and you see coaches talk to players, it's intense... I think fans love it, especially if you're watching on television. I think it adds to the sport."