Jakub Mensik had three break points midway through the fifth set on Louis Armstrong Stadium and did not convert any of them. It was the last real opening he got. Learner Tien held from 0-40, broke Mensik as the Czech served at 4-5, and closed out a 6-3, 1-6, 6-7(2), 6-3, 6-4 win shortly before 1:30 a.m. on Sunday to reach the US Open fourth round for the first time.
How Mensik got in front. The serve is the reason the 21-year-old is dangerous at this level, and in the third set it was close to untouchable: he gave up three points on his own delivery across the whole set and took the tiebreak 7-2 to lead two sets to one. He then broke first in the fourth. All he had to do from there was hold, and he could not. Tien won six of the next seven games to force a decider.
The fifth. Tien is now 5-0 in five-set matches in his career, and the shape of them rarely changes: the longer the match runs, the more the ground shifts under the man opposite him. At 0-40 on his own serve in the middle of the set he did not go for the lines to get out of it. He held, and Mensik got nothing else. Serving at 4-5, the Czech was broken to end it. “I wanna thank everyone here for staying this late,” Tien told the crowd on court afterwards.
The record. Tien is 20. The last American man to reach the US Open fourth round at that age was Andy Roddick in 2002, the year before Roddick won the tournament. Tien had never been past the first round in New York before this week; he arrived at Mensik having beaten Gael Monfils in straight sets in the second round, ending the Frenchman’s Grand Slam career. He is coached by Michael Chang, who won the French Open at 17.
Next. Karen Khachanov, who beat Benjamin Bonzi 6-3, 6-2, 6-4 earlier on Saturday. Tien is one of five American men in the last 16, alongside Tommy Paul, Frances Tiafoe, Ben Shelton and Alex Michelsen. For Mensik, a French Open semifinalist in June, the hard-court swing ends a round earlier than the draw suggested it might.
Read more: Learner Tien profile | Jakub Mensik profile
