Mark Selby said two poor sessions - and two key shots in the final session - caused his defeat by Ding Junhui in the World Championship quarter-final.
Selby trailed 10-6 going into the final session but levelled at 10-10 before Ding won three in a row to seal it.
"The first two sessions were very poor and I gave myself a lot to do but I think I played very well to come back to 10-10," Selby told BBC Sport.
"And I think I just played two wrong shots [in the next two frames]."
The Leicester man identified a missed red that would have put him 11-10 up, when he played for position instead of securing the pot, and an attempt to move a red out on the following frame, when he said he was in two minds and should have got up off the shot.
"If it wasn't for those two balls, I think I'd have won the match," he added.