It’s a reminder of a painful loss at the 2016 Olympics, and it’s likely the biggest obstacle Serena Williams will face on what seems to be her inevitable run to a historic U.S. Open victory.

But on Thursday night at Flushing Meadows, Williams will face the highest remaining seed in the women’s draw of the tournament, No. 5 Elina Svitolina.

Williams is looking for career Grand Slam No. 24, which would tie her atop the all-time list with Margaret Court, and would be her first major championship since giving birth to her daughter, Olympia, two years ago.

It would also be a bit of redemption for Williams’ controversial loss in last year’s U.S. Open final, when her spat with chair umpire Carlos Ramos was the story more than her disappointing defeat to Naomi Osaka.

But Svitolina, who already beat Williams’ sister, Venus, in the second round, has now made it to two straight Grand Slam semifinals after getting that far at Wimbledon in July. She is not just another player ready to be run over, and that’s highlighted by the memories of her career-defining victory over Williams in Rio de Janeiro three years ago.

“I played a great match,” remembered Svitolina, the quick-footed Ukrainian who will turn 25 next Thursday. “I was very young; not very young, but I was kind of young at the time. I didn’t have big wins at that time.

“For me, it gave me lots of confidence, as well, because I was playing really good sometimes. It gave me the confidence to actually let me believe that I can play consistent against the top players.”

Thus far, Williams has had a rather carefree run to the semis, brushing off a turned ankle with a dominant quarterfinal win over No. 18 Qiang Wang on Tuesday. Her tournament opened with a 6-1, 6-1 win over Maria Sharapova. Her only hiccup came when Williams dropped the first set against Caty McNally in the second round before winning the next two rather handily.

But Svitolina has elite-level skill when it comes to court coverage, a necessity against Williams’ overwhelming power.

“[Svitolina] is obviously a fighter,” Williams said. “She gets a lot of balls back. She doesn’t make a lot of mistakes. She’s one of those players that does everything really well. So I have to do everything well, too.”

Each of the top four women’s seeds already has been eliminated, with top-seeded Osaka losing in the fourth round to No. 13-seed, Belinda Bencic — who won again in the quarterfinals Wednesday and advanced to the semis as the second-highest seed remaining behind Svitolina.

As easy as Williams’ run has looked at times — she has lost just 22 games total — Svitolina has not dropped a set against her first five opponents.

And as unlikely as it is that Williams would let that old Olympics loss cross her mind, it does still remain as an unpleasant memory.

“That was a tough Olympics for me,” said Williams, who also lost with sister Venus in the first round of the doubles competition. “Just really devastated about that doubles loss. Then obviously singles shortly after.”

Williams then stopped and let out a wry smile.

“I didn’t play the Olympics in Rio,” she said jokingly.

Despite that being Sviotlina’s only win against Williams in five career matches, she still draws on it for confidence. It was the first time she really took advantage of the chance to beat a top player, and it helped propel her career forward.

“She gave me opportunities, for sure, in that match, and I actually took them and won the match,” Svitolina said. “It was a very special moment.”

Another special moment could await Thursday if Svitolina can convert another golden opportunity. Williams might look unbeatable right now — but she did three years ago in Rio, as well.

“I don’t try to up any intimidation factor,” Williams said. “I am who I am. I’ve always been the person that goes out there and roars and screams and complains and cries and fights. I’m extremely passionate about what I do. Most people that love their jobs are passionate about what they do. That’s just me.”