It's a shame he missed those 2 chances. One, well, he lacked class. Plain and simple. He could've done a Quagliarella vs Chelsea and get it between Casillas legs, if you watch it again you'll see if he had timed it right it could have been done.
The other was just a matter of momentum. Romário used to say there's very little chance for a gk to save when you head it to the ground, what it lacked was just power. It's a shame as those goals, or at least one more goal could have put us in a much more comfortable position.