Red Bull's Sebastian Vettel and McLaren's world champion Jenson Button shared the limelight on Friday in practice for an Italian Grand Prix both are desperate to win.
Button, shunted out of the previous Belgian Grand Prix by the German two weeks ago, went to the top of the timing screens in a sunny morning session at the super-fast Milanese circuit steeped in Formula One history.
Vettel, who has failed to convert his qualifying superiority into race wins, led the way in the afternoon in the former royal park where he took his first win with Toro Rosso in 2008.
The McLarens had set the pace for much of the session, however.
The 23-year-old German, who will be chasing his eighth pole in 14 races on Saturday, had been second fastest before lunch with a time just 0.097 slower than Button's best of one minute 23.693 seconds.
He cut the time to 1:22.839 with a low fuel run in the afternoon, with Ferrari's Fernando Alonso and Felipe Massa second and third. Button was fifth.
Championship leader Lewis Hamilton was third and fourth respectively for McLaren, who ran their cars with and without the 'F-duct' that enables a driver to stall the rear wing for greater grip.
There was little to choose between the two, with Button using the device and Hamilton not in the afternoon.
"The two different packages felt fairly similar," said Hamilton. "One is slower down the straights but quicker through the corners, and the other is quicker down the straights but slower through the corners."
"We haven't decided what to run tomorrow. It's about determining which is better on high fuel and whether there's more potential in one over the other."
WEBBER PROBLEM
Hamilton leads Red Bull's Mark Webber by three points in the standings with six races remaining. Vettel is third, a further 28 adrift, with Button fourth and 35 points off his team mate.
Webber was sixth fastest in the afternoon although he stopped with 18 minutes to go due to a water pressure problem.
"The car is going pretty well," said the Australian. "I have to find a little bit of lap time myself but the car is performing and I'm quite happy.
"We'll see how we go tomorrow but we're in the ballpark, which is nice. Ferrari look strong as well."
McLaren are clear favourites to win in Ferrari's backyard, with their car expected to be far more at home on the fastest circuit on the calendar than the Red Bull, which will be better suited to races to come in Asia.
Ferrari, with Alonso preparing for his Italian race debut for the glamour team and England soccer manager Fabio Capello as their guest in the garage, had made a slow start to the day with the Spaniard eighth and Brazilian Massa ninth.
Massa provided the big scare of the afternoon when he ran wide at the exit from Parabolica and kicked up a cloud of dust as he headed across the gravel.
"I tried to copy Kimi (Raikkonen) and do a bit of rallying," said Massa, referring to his former team mate turned world rally driver.
"Joking apart, I was really lucky when I went off the track... I kept the accelerator pressed down in the hope I would manage to avoid hitting a barrier and I managed it."
A healthy turnout of fans gathered for the first session, with a banner in Italian also welcoming the return of former Ferrari great Michael Schumacher.
"Michael we always wish you well," it read.
Schumacher, now with Mercedes at the age of 41 and after three years out of the sport, was 10th and 14th fastest.
Brazilian Rubens Barrichello, winner at Monza last season with Brawn GP and also with Ferrari in 2004 and 2002, parked up his Williams in the first session with a gearbox problem.
