Elena Rybakina needed two hours on court plus two one-hour rain interruptions to defeat Magdalena Frech 6-4, 7-6 (7/2) on Monday and reach the fourth round at the ATP-WTA Cincinnati Masters.
The second-seeded Kazakh admitted she struggled to close out a match which dragged on for much of the afternoon.
The players were forced off court after nine games of the first set and again in the seventh game of the second.
Upon the second return at the start of a week when rain is repeatedly forecast, two-time Grand Slam champion Rybakina was unable to wrap it up on three match points against the Frech serve in the 12th game.
With the Pole holding serve, the match went to a tie-breaker, where the seed finally got the job done on her fourth chance to get off court barely 10 minutes before more weather arrived.
Rybakina ➡️ Round of 16
— wta (@WTA) August 17, 2026
Elena Rybakina comes through a tough test against Frech 6-4, 7-6(2)!#CincyTennis pic.twitter.com/mcnCXuxFDw
"It was a crazy day, to be honest, coming out every time into clouds and humidity," Rybakina said. "I felt that I was on top of the ball in the tie-break, but it was a difficult one.
"I had the opportunities on the three match points but when you are tired it's difficult to keep concentration.
"I'm happy the tie-break went my way, I just tried to win as many points as I could."
Former world No 1 and defending champion Iga Swiatek was able to go through hours before the poor weather, turning the tables after losing the first set in defeated Maria Sakkari 4-6, 6-1, 6-1.
The Polish seventh seed, who won the Toronto title last week, improved to 6-4 over her Greek opponent, heading to the changing rooms after dropping the first set and returning as if another player.
Swiatek, winner of six Grand Slam titles including the US Open four years ago, only lost two more games after her remarkable turnaround.
The seventh seed needed two hours to complete her reversal in form, saving seven of eight break points while breaking Sakkari five times. The Greek hit the net with a return on Swiatek's first match point.
Swiatek 🤝 Stadium@iga_swiatek outlasts Sakkari for a place in the Round of 16!#CincyTennis pic.twitter.com/ywIguKMmfb
— wta (@WTA) August 17, 2026
'LACKED PRECISION'
"It's hard to analyse this match," Swiatek said. "I was playing good in the first set but I lacked precision, I was playing too much to her.
"After that I wanted to push her and not give so many opportunities. I'm happy it started working in the second set I played a bit better.
"She made mistakes and the momentum changed a little bit."
Swiatek moved into a match against Diane Parry, winner of an all-French battle with Lois Boisson 4-6, 6-4, 6-3.
In the men's draw, Thiago Tirante maintained his pace after ousting Novak Djokovic in the second round with the Argentine advancing past Spain's Martin Landaluce 7-6 (7/5), 7-6 (7/4) to reach the third Masters round of 16 in his career.
Roland Garros finalist Flavio Cobolli came from a break down in the deciding set to defeat Alexander Blockx 7-5, 4-6, 7-5 and avenge a loss to the Belgian in Monte Carlo.