Grigor Dimitrov has apologised for smashing his racquet three times during the final set to concede the Istanbul Open final to Diego Schwartzman.
The Bulgarian, seeking his first title in two years, lost 6-7 (5-7) 7-6 (7-4) 6-0, having been a set and 5-2 up.
Dimitrov received a warning for his first racquet smash, early in the third set, then a point penalty for another.
That left him 5-0 down, before a third offence incurred a game penalty, which gave his Argentine opponent the match.
"I let my family down, I let my team down, I let my fans down with that kind of behaviour which I definitely apologise for," the world number 29 said.
After his third racquet smash, number two seed Dimitrov shook hands with umpire Mohamed Lahyani.
The 24-year-old's behaviour handed unseeded Schwartzman, 23, his first ATP Tour title.
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