Stefanos Tsitsipas says he lost to Dominic Thiem because of the 'silliest' decision he believes he has ever made.
Tsitsipas is the defending champion in London after he beat Thiem in the final last year.
The Austrian gained some semblance of revenge by winning their opening round robin clash on Sunday, although Tsitsipas lamented one shot he played in the crucial first-set tiebreak when he was a mini-break up.
“That was the silliest thing that ever happened to me,” Tsitsipas explained.
“I had a ball over the net, and I decided to play a forehand instead of a smash,” Tsitsipas said.
“I don’t know what kind of decision that was, but it was very… it was not mature enough, you know?
“Didn’t take time, just rushed and didn’t take time to think where I wanted to go and I used my strongest shot.
"He ended up blasting me with a lob, and I was in a defensive position afterwards.”
Comparing the match to the final last year, Tsitsipas added: “He dealt with my serve better and took time [away], he stepped back and applied the pressure.
“He put more pressure on me. Some of the second serves that I had early in the third set… and I think that paid off for him.”
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