Sam Querrey of the United States took the last nine games and upset No. 5 seed Dominic Thiem 6-7 (4), 7-6 (1), 6-3, 6-0 to make the French Open runner-up the third top-10 man already gone in Wimbledon's first round.
The 65th-ranked Querrey was one point from falling into a two-set deficit while serving down 5-4 in the second. But he held on there and then took a lead by getting his initial break of the match in the third set.
Thiem has lost to Rafael Nadal in the final at Roland Garros each of the past two years. He is a lot less comfortable on grass: This was the Austrian's third first-round exit in six appearances at Wimbledon.
He joined No. 6 seed Alexander Zverev and No. 7 Stefanos Tsitsipas on the sideline after they each lost a day earlier.
Querrey's only Grand Slam semifinal appearance came at the All England Club in 2017 after a victory over defending champion Andy Murray. Querrey defeated Novak Djokovic a year earlier at Wimbledon.