He almost got caught but didn't. But the game was super tight. Samp had everyone behind the ball. We saw in the 2nd half when the game opened up, did Melo screw up our attack? Not at all.
But his destruction of Samp's midfield is what's most important. By the end of the game they were turning away from his challenges. That stuff is important. It helps create our identity as a fast, physical team.
No one is perfect, lots of players make mistakes in a game. Del Piero lost the ball 5 times. Pepe crossed it into a defender 5 times. De Ceglie and Motta got turned around like revolving doors all game. Melo slipped and fell and made one bad pass.