Given his radically impressive form, there is only one way Lionel Messi can fail to influence a game: lack of touches.
Even when Barca are dominating possession, the Argentine always runs the risk of going long stretches without touching the ball because he prefers to play as the center forward.
Against the organized 4-5-1 deployed by Massimo Allegri, Messi was forced to receive the ball farther and farther away from goal.
Why? Because as his teammates were frantically switching positions and making runs, Messi continued to walk around expecting a perfect pass to be delivered. But it never came.
At the San Siro, it was obvious for all to see. While none of Barcelona's players will admit it, Messi's petulant movement sometimes causes a problem in a congested midfield.
If he doesn't improve his movement off the ball at the Camp Nou in 3 weeks, the world's most talented team could see themselves eliminated by a mediocre AC Milan side.