Ben Shelton apologized after hitting a Wimbledon ball kid with a high-speed serve during his first-round match against Otto Virtanen.
The incident occurred on Court Two when Shelton's ferocious serve caught the ballboy off-guard.
What happened?
Shelton's serve, which reached 146mph, accidentally hit the ballboy in the midriff.
The American immediately put his hand up to apologize and was heard saying: "Are you OK."
The ballboy assured Shelton he was fine before the American returned to the baseline to continue playing.
Why it matters for Ben Shelton
Shelton, who reached the quarter-finals at Wimbledon last year, was looking to make a deep run in the tournament.
However, he was dumped out by qualifier Virtanen in a major upset, losing in five sets.
The result means Brit Arthur Fery will face Virtanen in the second round instead of Shelton.
What comes next?
Shelton will look to bounce back from his early exit at Wimbledon.
He had endured a nightmare French Open, being dumped out in the second round in straight sets.
The 23-year-old will aim to regain his form and make a strong run in his next tournament.
Shelton's high-speed serve has been a key part of his game, and he will look to use it to his advantage in future matches.
The American has registered the second fastest serve of the tournament, with only Thiago Agustin Tirante recording a faster serve at 147.8mph.
Virtanen's win over Shelton has earned him a prize money of £126,000.
He will face Brit Arthur Fery in the second round, who became only the second Brit to make it through to the next round after Katie Swan.
Fery had a fiery four-set win over Damir Dzumhur, with the Bosnian calling out Fery and the umpire in a fit of rage at one point.
Fery said afterwards that he expected Dzumhur's behavior, saying: "He does that with everyone.