McLaren was fastest in the morning practice session, Red Bull in the afternoon, while Ferrari's F10 was just hundredths of a second off the pace.

Mark Webber, 3 points adrift Lewis Hamilton's title lead, had a slight afternoon scare with a water pressure alarm.

"We had to turn off the engine to prevent any damage," said the Australian.

"It's going well.  I need to find some pace in myself but we're on the pace," he is quoted by German media.

Last year when KERS proved an additional handicap to Red Bull's power disadvantage, Monza was a poor circuit for the Austrian team but "it looks much better this year", said Sebastian Vettel, the fastest around the Autodromo Nazionale on Friday.

"McLaren look extremely strong," said the German, "and Ferrari are strong as well."

Fernando Alonso confirmed: "We are there."