It was a turbulent few months for Swiatek. After losing to Pegula in the quarterfinals of the US Open, she changed coaches and sat out the Asian swing. Here in Riyadh she came back from a set and two breaks before defeating Krejcikova. Her straight-sets loss to Gauff confirmed that she wasn’t in top shape, at least mentally. Her frustration was obvious from the start.

“I had to kind of keep my head on a leash and constantly check it,” Swiatek told reporters. “So I haven’t had these difficult moments in two months. So I kind of forgot what it was like and how much energy it took.

“It’s a reminder that nothing comes for free. You always seem to be working 100 percent because in tennis the dynamics can change pretty quickly. You have to be consistent throughout the game to win.”

Schedule for day 6

1 p.m. local time

(2) G. Dabrowski (CAN) / E. Routliffe (NZL) vs. (5) C. Dolehide (USA) / D. Krawczyk (USA)

Not before 3:30 p.m

(2) I. Swiatek (POL) versus (6) D. Kasatkina

Not before 6 p.m

(3) C. Gauff (USA) vs. (8) B. Krejcikova (CZE)

Followed by

(4) S. Errani (ITA) / J. Paolini (ITA) vs. (7) H.-C. Chan (TPE) / V. Kudermetova

Game breakdown

No. 2 Iga Swiatek (1-1) vs. (ALT) D. Kasatkina

Head-to-head: 5:1, Swiatek

Last game: Swiatek defeated Kasatkina 6-2, 6-3 in the 2022 WTA Finals in Fort Worth

Swiatek was scheduled to face Pegula before the five-time major champion withdrew, presenting a potentially tougher test against the fresher Kasatkina, currently ranked No. 9 in the world.

Kasatkina won her first career meeting in Eastbourne in 2021, but Swiatek has won the last five meetings, four of them on hard courts – including a decisive win in Fort Worth two years ago.

Kasatkina has a 40-22 season record, with her last game in Tokyo ending in a quarterfinal loss to Sofia Kenin. However, she put together a solid fall, highlighted by a three-set win in the Ningbo final – her second title of the year.

On the other hand, Swiatek has lost four straight games this year against top 10 players – Zheng Qinwen (Paris Olympics), Aryna Sabalenka (Cincinnati), Pegula (US Open) and Gauff (WTA finals) – the longest series of this kind in her career.

No. 3 Coco Gauff (2:0) against No. 8 Barbora Krejcikova (1:1)

Head-to-head: 1-0, Krejcikova. Her only previous match was a barnburner at the 2021 French Open.

Krejcikova saved five set points in the first set and defeated the 17-year-old Gauff 7-6 (6), 6-3 to advance to the semifinals. In only her fifth appearance in a major singles draw, Krejcikova claimed her first Grand Slam singles title by defeating Anastasia Pavlyuchenkova in a three-set final.

The fact that Krejcikova finds herself in this position is unimaginable.

No player of this century has made it to the WTA final with fewer than 30 match wins. Krejcikova, plagued by injuries, has just played 31 games this year.

What would it mean to reach the Final Four of the year-end tournament after such a difficult season?

“It would definitely be great to progress and play more games,” Krejcikova said. “So I’m going to do everything in the game to get there.”

She went above and beyond against Pegula, hitting 11 aces and breaking them four times.

Gauff had lost 11 of 12 games against Swiatek before breaking through with a 6-3, 6-4 win. Perhaps coincidentally (maybe not), Gauff has now won 11 of her last 12 games.

She worked on her serve and it was tough against Swiatek.

“I’m in the process of changing things, so it’s up and down, and I feel like it’s going in the right direction,” Gauff said. “The first set, no break points, and I don’t even know if that (Gauff) ever happened against her.

“The first WTA final (Fort Worth, 2022) I was 0-3, and now that I’m 2-0 it’s pretty cool. Hopefully I can win three more games and finish the season.”