Emma Navarro was broken twice in four games in the second set on Friday and won the set anyway. She broke Karolina Muchova at 5-5, held to close it out, and put the seventh seed out of the US Open 6-3, 7-5. Neither woman could keep hold of a service game in the middle of that second set. Navarro broke in the third to lead 2-1 and was broken straight back.
She broke again in the fifth for 3-2 and was broken back again in the sixth. Five of the first eleven games went against serve. Then, at 5-5, Navarro built three break points and converted the third, and served the match out from there. The first set had followed a similar shape without the same volatility. Navarro broke in the fourth game and again in the eighth, Muchova got one back in the fifth, and Navarro took it 6-3 having won 40 of the 69 points.
The break in the eighth came on a misfiring Muchova forehand, one of 22 unforced errors the Czech made in that set alone. She converted only two of seven break points in that set and three of five in the second, which is the difference between a match that stayed close and one that did not.
Muchova came into the tournament in an unusual condition. She had minor surgery after finishing runner-up at Wimbledon in July and played no hard-court warm-up events at all, arriving in New York with a 20-4 hard-court record for the year built entirely before the break. She then won the US Open mixed doubles title with Jakub Mensik the week before the singles began, and dropped four games across her first two singles rounds, beating Sinja Kraus and Katie Boulter without difficulty. Friday was the first time in New York that anyone made her play a competitive service game.
Navarro arrived from the opposite direction. The 26th seed has had a losing hard-court season and had already been taken to three sets twice here, edging Lois Boisson 7-6, 6-7, 6-3 in the first round and recovering from a set down against Caty McNally 3-6, 6-2, 6-3 in the second. She had spent six sets to Muchova’s four, and it was the player with the heavier legs who held the important game.
Muchova had gone at least as far as the quarterfinals in each of her three previous US Opens, the semifinals in 2023 and 2024 and the last eight in 2025. She arrived this year ranked No. 7 with a Grand Slam final already behind her, and she leaves in the third round. Navarro, a semifinalist here in 2024 and a third-round loser last year, is back in the second week of a major, and it is her third win over a top-ten opponent this year.
“I knew it was going to be tough today,” she said. She will play Elina Svitolina or Anna Kalinskaya in the round of 16.
