It's all in his mind
Sergio hits all his clubs, from Driver to wedges, as well as Tiger or anyone else. His short game (not including putting) is excellent. His putting used to be deficient, but he looked a lot better with the belly putter, especially in rounds 1 through 3.
However, mentally he doesn't stand a chance. His ball-striking talent allowed him to contend despite his warped attitude, but in the end the mind game did him in.
His pessimism and "the universe is out to get me" attitude will guarantee he will never fulfill the promise of his great potential. Padraig said he "knew" he was going to win all week, even when he hit it in the burn twice on the 72nd hole.
Unfortunately, Sergio was a train wreck waiting to happen. He is always looking for the Golf Gods to get him, and it becomes a self-fulfilling prophecy. In that respect, he is not too dissimilar from Monty.
If he could somehow come around to a positive attitude, he has the game to challenge anyone....but I think it is unlikely.