It will be intriguing to see whether the man engaged in one of sport's greatest comebacks, Roger Federer, will compete in the French Open next month.
Federer, now 35 and thought by most of us to be slipping into irrelevance after missing half of last year with knee injuries, has had an astonishing 2017 so far - winning the Australian Open and two other titles and beating his nemesis, Rafael Nadal, in all of them.
In doing so, Federer has shown an old dog can most certainly learn new tricks. His backhand, an elegant single-handed stroke - rare in these days of double-handed, power topspin - has transformed his game.
Previously, Federer has mostly employed a slice backhand, undercutting the ball. It's a tactic players use when they want the security of not over-hitting their return; a sliced backhand never overpowers opponents but mostly stays in court, keeping the rally alive.
Nadal, in a decade of dominance over Federer, would wait for that backhand like your dog waits for something to fall off the table at family meals. He'd pounce, subject it to a nasty savaging with his top-spun forehand and generally win the point ... and the game ... and the set ... and the match.
No longer. In his last victory, at the Masters tournament in Miami, Federer blazed single-handed topspin backhands past a helpless Nadal to win 6-3 6-4. So why hasn't Federer done this before and how has he learned to do it at such an advanced age (for a world-class tennis player)?
Firstly, Federer has finally come to terms with using a racquet with a larger head. Most importantly, coach Ivan Ljubicic has helped him over the considerable physical and mental block of his backhand.
Still only 38 himself and a former world No3, Ljubicic had a single-handed backhand himself - but more aggressive and generally using more topspin. You can see that backhand in Federer's arsenal now.
Ljubicic has worked with the Swiss until he is confident enough to bring out the boom-boom backhand earlier and more often. Previously, Federer mostly played the slice unless he was demonstrably on top or had settled into his rhythm during a match.
The new backhand means he can deal better with high-kicking shots from opponents, making his game far more attacking and giving the guy on the other side of the net less time.
It's not the only change Federer has made. His season game plan depends on him missing tournaments, being fresh as he moves through the year. He's said he will not play the clay court season which begins now - except for the French Open at Roland Garros, beginning on May 22. Some of his ATP rivals think he may not play at all.
"I'm not 34 any more, you know," he joked after Miami. "I want to play, if people see me, that they see the real me and a guy who is so excited that he's there. So that's a promise I made to myself ... if I play tournaments, that's how my mindset has to be."
He hadn't played for seven months when he won the Australian Open and, ahead of his win at Indian Wells, he played two tournaments in five weeks. His energy levels, speed and endurance have been superior to far younger men plodding on the heavy treadmill of the ATP tour week-in, week-out.
Federer may not win the title of the greatest tennis comeback of all time - that probably still belongs to Australia's Margaret Court who retired at 24 to get married after winning Wimbledon in 1966, her 13th grand slam title. Two years later, she returned and in 1969 remarkably completed a calendar year grand slam, winning all the major titles.
However, he may reclaim the unofficial title of the best of all time. Nadal's dominance dented that, as did the emergence of clear world No1 Novak Djokovic and recent successor Andy Murray. Both have been injured lately and their future clashes with the resurgent Swiss are to be savoured.
Federer's 18 grand slam titles (Nadal and Pete Sampras have 14 each and Djokovic 12) could yet be extended and maybe he will nudge up to 20, cementing "the greatest" label. He is also threatening Ken Rosewall's freakish record of longevity; the little Australian, ironically known as "Muscles", won the Australian Open in 1953 and again in 1972 (he was 37); he won the US Open in 1956 and again in 1970 and the French Open in 1953 and 1968.
Rosewall, however, never won Wimbledon (though he appeared in finals that were, incredibly, 20 years apart). Federer was 22 when he first won Wimbledon; it is not beyond the realms of possibility that, if his body holds together in his "freshness" strategy, he could do a Rosewall.
That would be some kind of legacy.