Well, it's already been a pretty costly day for Phil Mickelson ... that $200,000 bet with Tiger Woods didn't exactly go his way.
Remember, earlier this week, Phil bet Tiger $100,000 that he would birdy the 1st hole at the big pay-per-view golf match on Friday. Tiger was so confident, he told Phil to "double it."
Phil didn't completely botch the hole -- he had a perfect opportunity to win the bet ... but when he hit the putt that woulda given him the birdy, it stopped short.
He hit the next shot for par -- but the damage had already been done.