Jenson Button leads opening Italian GP practice

MONZA, Italy (AP) - Jenson Button was fastest in the opening practice session for the Italian Grand Prix, and McLaren and Red Bull lived up to the favorites billing while Ferrari lagged behind.

Button's lap of 1 minute, 23.693 seconds in his McLaren was one-tenth of a second faster than Red Bull counterpart Sebastian Vettel. Overall Formula One leader Lewis Hamilton was third for McLaren.

Mark Webber of Red Bull was sixth, and Ferrari pair Fernando Alonso and Felipe Massa were eighth and ninth, respectively. Alonso was nearly nine-tenths off the pace.

Hamilton leads Webber by three points going into Sunday's race, while third-place Vettel is 31 points behind the leader. Vettel, Button and Alonso are separated by only 10 points.