Fourth-round action at the U.S. Open resumes on Monday. By the end of the night, all of the quarterfinal spots will be determined. Among those taking the court are Alexander Zverev, Learner Tien, Coco Gauff, Iga Swiatek and Naomi Osaka.
Here are my picks for two of Monday’s best matchups.
Karen Khachanov vs. (14) Learner Tien
The host nation figured to have a semifinalist in the top half of the U.S. Open men’s singles draw. It still might — but after Taylor Fritz fell to Francisco Cerundolo on Saturday, Tien is now the American man expected to make it that far (along with perhaps several others in the bottom half). The world No. 15, who was an Australian Open quarterfinalist near the beginning of 2026, has continued his stellar form with victories this fortnight over Nuno Borges, Gael Monfils, and Jakub Mensik.
Up next for Tien is Khachanov, whom the left-hander has never faced. Khachanov is into the fourth round at the BJKNTC for only the second time, and it has come as a surprise, too. After all, the 30-year-old had been a disappointing 16-18 this season prior to arriving in NYC and is down at No. 50 in the world. Khachanov appears to be getting back on track with defeats of Roman Andres Burruchaga, Felix Auger-Aliassime, and Benjamin Bonzi, but that was a very favorable Week 1 draw — at least when you factor in Auger-Aliassime’s struggles. A matchup with Tien will almost certainly be tougher.
Pick: Tien in 4
(1) Alexander Zverev vs. (21) Luciano Darderi
Zverev was the marathon man at the U.S. Open through two rounds, spending nine hours and 26 minutes on court against Lorenzo Sonego and Quentin Halys. Sonego was even two points from the upset in round one. Zverev is still alive, however, and now he should be in much better shape moving forward after requiring just two hours and 26 minutes to see off Alejandro Tabilo 6-2, 7-6(2), 6-2 on Saturday.
The second-ranked German now faces Darderi, with the H2H tied 1-1. Zverev got the job done 7-6(3), 6-2 at the 2024 Rome Masters 1000 before Darderi scored a 1-6, 7-6(10), 6-0 surprise at that same event earlier this season. The Italian had little trouble advancing through his first three rounds at Flushing Meadows. He surrendered only two sets in total while dismissing Harry Wendelken, Dalibor Svrcina, and Dane Sweeny. Needless to say, though, that was an absolute dream of a Week 1 draw for the world No. 22. Such good fortune, of course, runs out with the U.S. Open’s top seed on the other side of the net.
Pick: Zverev in 3
Ricky contributes to 10sballs.com and also maintains his own tennis website, The Grandstand. You can follow him on Twitter at @Dimonator.