Ivo Karlovic accused the line judges at Wimbledon of favoring Andy Murray after they called a number of foot-faults against the hard-serving Croat on Centre Court.
Karlovic, who lost, said some of the calls were "outrageous" and that "after this match, the whole credibility of this tournament went down for me."
Murray edged Karlovic 7-5, 6-7 (5), 6-2, 7-6 (4) Thursday to reach the third round.
Karlovic said "it was always when it was 30-all or in a tiebreak. I mean, what is this? Is it Davis Cup or is it Wimbledon?"
Murray said he wasn't sure whether the calls were correct but that "if he wasn't foot-faulting then he has a right to be upset, because there was a lot of them."