MONZA, Italy (AP) Lewis Hamilton's hopes for a grand slam repeat at the Italian Grand Prix ended after the first practice on Friday.
The Formula One champion was edged by Mercedes teammate Nico Rosberg by 0.203 seconds.
Last year, Hamilton led each practice, took pole position, and led the race from start to finish.
Running on Pirelli's new supersoft tires, Rosberg's time was slightly better than Hamilton's pole time last year.
Ferrari's Kimi Raikkonen and Sebastian Vettel placed third and fourth, respectively.
Rosberg won the Belgian GP last weekend to cut Hamilton's championship lead to nine points.
While Hamilton has won the Italian GP three times, Rosberg is still seeking his first victory at the legendary track outside Milan, which has hosted more F1 racing than any other circuit.
Hamilton is aiming for his 50th career win in Sunday's race.
Max Verstappen, Jenson Button, and Sergio Perez tested out a protective halo device designed to reduce the risk of head injuries, following the deaths of F1 driver Jules Bianchi and British IndyCar driver Justin Wilson last year. The halos could be introduced for races in 2018.
Verstappen, the 18-year-old who won the Spanish GP, was eighth.
A day after announcing he will retire after this season, Felipe Massa encountered a technical problem with his Williams. Massa spent a large part of the session in the garage before eventually placing 14th.
Kevin Magnussen, fresh off a frightening crash in Belgium, had another problem on the 180-degree Parabolica, but escaped any more damage in his Renault.
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