NEW YORK -- No. 26-seeded Sam Querrey was upset in the second round of the U.S. Open.
Adrian Mannarino beat the American 7-6 (4), 7-6 (5), 6-7 (5), 6-4 on Thursday. The 63rd-ranked Frenchman reached the fourth round at Wimbledon this year.
Querrey's best run at Flushing Meadows was making the fourth round in 2008 and '10. He advanced to the third round at the Australian and French Opens this year.
There were only three breaks of serve in the match, but Mannarino got one at 5-4 in the fourth set to clinch the victory.
Querrey had 25 aces but seven double-faults. The players combined for 117 winners and 106 unforced errors.