She has still been present on tour to a degree.

“She’s been the best female tennis player ever and of course everybody’s speaking about her even when she is not here,” said Wim Fissette, who coaches Angelique Kerber.

With social media, Williams can be as much a part of the daily conversation at a tournament as she likes, and she weighed in on occasion during the Australian Open.

She congratulated her friend Caroline Wozniacki for winning her first Grand Slam title and, earlier, she called out Tennys Sandgren, the surprise men’s quarterfinalist from the United States, for past comments he had made on his own social media accounts. Sandgren’s Twitter activity — since deleted — included exchanges with figures from what is known as the alt-right, a far-right, white nationalist movement; a post saying his eyes were “bleeding” after a visit to a gay club; and a post apparently critical of Williams that used the term “disgusting” and may have been referring to her screaming on court.

Williams, increasingly activist in her public statements in recent years, will soon be a physical presence on tour again, not just a virtual one. Her only competition appearance in the last year was a lucrative, one-match exhibition in Abu Dhabi in late December, which she lost to Jelena Ostapenko.

It is quite a juxtaposition: Federer, the biggest star in men’s tennis, taking a break while Williams, the biggest star in women’s tennis, returns to action. But it underscores how complementary the men’s and women’s games can be, a symbiotic relationship that remains one of the sport’s core strengths. Though there are distinctions, men’s tennis and women’s tennis are viewed as the same product by many who tune in only during the year’s biggest tournaments.