Kei Nishikori felt he defeated himself at the Australian Open, with the seventh seed lamenting his failure to convert his chances against world number one Novak Djokovic on Tuesday.
Nishikori was eliminated 6-3 6-2 6-4 by defending champion Djokovic in the quarter-finals at Melbourne Park, though he was not without opportunities on Rod Laver Arena.
The Japanese had eight break-point chances but only managed to convert two, both coming in the third set.
Speaking afterwards, Nishikori felt the last-eight defeat was a result of his wayward performance, rather than Djokovic's brilliance.
"I sort of had a good start. But when I lost the [sixth] game with my serve, everything started changing," said the 26-year-old.
"He started playing much better. I lost a little bit confidence, started missing a lot.
"That was really important game that I lost. But he played a good level. He's playing good tennis again.
"I had some chance in third set, but couldn't keep up my level. I am really disappointed for my game. But he played good tennis.
"He returned well. I rushed a little bit, too. I was missing some easy shots that I shouldn't miss. The third set I had most of chance, but I couldn't convert."
Nishikori added: "I think today was more my game. I was missing too much, especially first couple sets.
"I lost many easy games. I couldn't make him work hard today. He is playing good. But I couldn't play good tennis today."