I've heard a few of these through the years. they mostly tend to be self defeating sounding.
The pool G-d's must be giving you all the luck.
Damn it, if we were playing for money I wouldn't have dogged that shot!
Damn it, if we were playing for more money I wouldn't have dogged that shot!
Damn it, if we were playing in a tournament I wouldn't have dogged that shot!
Damn it, if they rated me right I wouldn't have dogged that shot!
Wasn't enough pressure on that game to make me shoot well.
There's no way you just beat me, you must have cheated.
I'm sandbagging to keep my spot low===> this was in an open tournament...lol
It must just not be my day.
I couldn't hit the broad side of a barn if I tried.
My glasses prescription must be bad if I missed that shot.
First day with the new eyes.
I would have won if I had brought my other cue....This guy only had one cue and played with it all the time.
I lost because I suffer from HUA....head up A$$
It wasn't you winning it was me losing. I beat myself!----can be true

but does that have to be said to your opponent.
Guy gambling for decent stakes and losing says, "I can't play this game. I'm a ping pong and darts guy really."
I would have won but you had an advantage with that fancy custom cue.