Tennys Sandgren was disqualified after just two games at the ATP Challenger event in North Carolina after he accidentally hit a line judge with a ball, moments after he was struck in the groin by a throw from a ball boy.
Sandgren, 30, who was the top seed at the tournament, admitted the turn of events was "all totally my fault".
The American was struck by a ball bounced to him as he prepared to serve against compatriot Christopher Eubanks, with the ball boy immediately saying "sorry".
Sandgren then angrily swatted away the ball, which hit a line judge on the backside after ricocheting off a fence, earning him a default.