They've played each other 10 previous times, with Williams winning nine, including a three-setter at the Australian Open in January.

"I respect a lot what she has done and what she's doing," said Halep, who, like Williams, used to be ranked No. 1. "But now I feel stronger, mentally, facing her. We will see what is going to happen. It's just a big challenge for me."

For anyone, really, when Williams is at her best.

And after an up-and-down first half of the year, due in part to injury and illness, she sure does appear to have lifted her level considerably.

Williams was limited to 12 matches in 2019 until last week. After a third-round loss at Roland Garros on June 1, she stayed in France for medical treatment and finally felt pain-free while preparing for Wimbledon.

"Well, if she will play like this in the final," said Strycova, 33, the oldest first-time Grand Slam semifinalist in the modern era, "it's going to be very hard for Simona."

After a three-set struggle against Alison Riske in the quarterfinals Tuesday, Williams was dominant against Strycova, who was limited by a leg muscle problem that cropped up in the very first game.

Strycova would repeatedly flex or shake her legs between points or try to stretch in her sideline chair by pulling her right foot onto her left knee and rocking her leg.

Not an ideal situation. Especially when facing Williams if she's this dialed-in.

Williams played cleanly, accumulating nearly twice as many winners as unforced errors, 28-10. She was at her usual court-covering best, which helped limit Strycova to 10 winners.