The No. 22-seeded Stan Wawrinka lost his second-round match at Wimbledon to a 21-year-old American tennis player Wednesday.

Reilly Opelka, 21, defeated the three-time Grand Slam champion Wawrinka 7-5, 3-6, 4-6, 6-4, 8-6.

CLICK HERE FOR COMPLETE WIMBLEDON COVERAGE

“At first I had a lot of success serving and volleying, so I kept with that,” he said. “And then as he kind of picked up on what I was doing and started reading my serve a little bit, it was more difficult for me to win points at the net. So I had to play, played a lot of tennis on the baseline today.”

Opelka will be making the third-round of a Grand Slam even for the first time in his career. It’s his first time playing at Wimbledon and only his fourth Grand Slam tournament appearance.

CLICK HERE FOR MORE SPORTS COVERAGE

Wawrinka admitted he started slow.

“I had some chance.” he said. “I start a little bit slow. I was a bit hesitating, not really moving well enough. ... At the end he went for it. He went bigger than me and he deserved to win.”

CLICK HERE TO GET THE FOX NEWS APP

Opelka faces the 2016 Wimbledon finalist Milos Raonoic next.

The Associated Press contributed to this report.