Serena Williams shakes hands with Ajla Tomljanovic after their match in...

Serena Williams shakes hands with Ajla Tomljanovic after their match in the third round of the U.S. Open on Friday. Credit: Newsday/J. Conrad Williams Jr.

The hardest thing to envision is the day after — that’s what a lot of professional athletes say. After having years of their lives fully dictated by a sport, few can imagine what it’ll be like the day after retirement, when there’s that giant chasm to fill.

Serena Williams didn’t have that problem.

“I’m definitely resting tomorrow,” she said Friday, as if it were something she’s been waiting to say for 25 years. “Then probably spending some time with my daughter.”

There were times after her U.S. Open third-round loss to Ajla Tomljanovic when Williams seemed to waffle on her decision to retire (she has used the word transition rather than retirement).

She was surprised by how good she felt, how much stronger she had gotten, how much more she would be able to accomplish. But when it came down to it, Williams, who will turn 41 this month, said a comeback is unlikely.

She had a new purpose to dedicate herself to — a purpose that made the “day after” question so easy to answer. It sounded a lot like Olympia, her daughter.

“I’m ready to be a mom, explore a different version of Serena,” she said. “Technically, in the world, I’m still super-young, so I want to have a little bit of a life while I’m still walking . . . I’m a super-hands-on mom. I’ve been with her almost every single day of her life, minus two days or three days. It’s been really hard on her, my career. So it will be nice just to do that and spend some time with her, do things that I never really have done or had an opportunity to do. I have such a bright future ahead of me.”

In a world in which professional athletes are viewed and evaluated by the prime of their careers, Williams showed she has her eyes set on a different sort of prime. It’s one in which she can dedicate herself to her family and, she said, likely have some involvement in tennis.

The stillness of the pandemic and the year off she took off in 2021 while nursing a leg injury she suffered at Wimbledon helped her make the decision.

“I think it means so much to me in my life, and I’ve had so many amazing moments, that I don’t see a future without it,” she said. “What’s my involvement? I have no idea. I think I’ll be involved in some way or shape.”

That certainly sounds promising to those still in the sport, including Williams’ opponent Friday, who defeated her and then feted her.

“I’m feeling really sorry because I love Serena just as much as you guys do and what she’s done for me, the sport of tennis,” Tomljanovic said. “I never thought I’d have a chance to play her in her last match when I remember watching her as a kid.”

Despite being in a nearly impossible position, the Croatian-Australian more than rose to the occasion, even if it took her three sets and six match points in the final game to do it. She not only battled the best player of all time, albeit one 11 years older than she is, but an Arthur Ashe Stadium crowd that was intent on willing Williams to victory.

“I just thought she would beat me, so, you know, the pressure wasn’t on me,” Tomljanovic gamely told the crowd. “She’s Serena. Even until the last point, I knew she’s in a really good position to win even when she’s down 5-1 . . . She’s the greatest of all time. Period.”

She was fully cheered then, and for the first time all night.

In her post-match news conference, Tomljanovic broke down her internal conflict. The athlete in her wanted to win. The tennis lover in her wanted Williams to play another day.

“I would be cheering for Serena, too, if I wasn’t playing her,” she said. “But it was definitely not easy. There was no other way.”

Serena Williams — the ultimate competitor — would wholeheartedly agree.

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