Less than five months ago, Serena Williams needed just 44 minutes to bounce China’s Wang Qiang out of the U.S. Open, a 6-1, 6-0 quarterfinal thumping in which the tennis legend won 50 points to only 15 for her challenger.

On Friday in the third round of the Australian Open, the numbers were not on Williams’s side: In a match that lasted 2:41, the eighth-seeded Williams made 56 unforced errors and saw her hopes of a record-tying 24th grand slam singles title end much earlier than anyone could have possibly anticipated in a 6-4, 6-7 (7-2), 7-5 loss to Wang, the No. 27 seed who advanced past the third round at a grand slam singles event for only the second time in her career.

It was Williams’s earliest exit at the Australian Open — a tournament she’s won seven times — since 2006, and afterward, the 38-year-old said that at her age, she can’t afford to make so many mistakes.

“I’m way too old to play like this at this stage of my career,” Williams said, per the Associated Press. “Definitely going to be training tomorrow, that’s first and foremost — to make sure I don’t do this again.”

The match almost was over much earlier. Wang dominated the first set, saving all four break points she faced, accumulating 10 winners and making just five unforced errors, and was serving to end it up 5-4 in the second. But Williams broke Wang for the first time in six tries and then dominated the tiebreaker to force a third set.

“I was optimistic that I would be able to win,” Williams said. “I thought, ‘Okay, now finish this off.’ I honestly didn’t think I was going to lose that match.”

That she did indeed lose the match raises the question of whether Williams will ever be able to catch Margaret Court and her 24 all-time grand slam singles titles. Though she reached the final of the previous two slams, it’s now been three years since she last won one, at the 2017 Australian Open when she was pregnant with daughter Alexis.

“I didn’t return like Serena. Honestly, if we were just honest with ourselves, I lost that match,” Williams said. “I can’t play like that. I literally can’t do that again. It’s unprofessional. It’s not cool.”

A highly anticipated fourth-round match between Williams and close friend Caroline Wozniacki now is off the table, with neither able to survive the third round. Wozniacki, the 2018 Australian Open champion who was playing in her final tournament before arthritis-induced retirement, bowed out of the tournament and competitive tennis at nearly the same time as Williams, suffering a 7-5, 3-6, 7-5 loss to 78th-ranked Ons Jabeur of Tunisia.

Williams told reporters after her match that she and Wozniacki “were both kind of bummed” together in the locker room following their losses and tried to stem her emotions when talking about “one of my best friends in the world.”

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