Charlie Sheen -- I Know What's Wrong with Tiger Woods ...

Call him Dr. Charlie ... 'cause the warlock tells TMZ Sports he's diagnosed Tiger Woods -- and says he knows exactly why the golfer can't seem to pull it together on the links.

Sheen was takin' in a movie at The Grove Wednesday night ... when he told us the issues with Tiger aren't mental, it's more physical ... insisting the tooth wasn't the only injury he suffered during that fateful night with Elin in 2009.