Despite several drivers claiming the track was more like a rallycross venue thanks to its lack of recent use, oil from support races and slight drizzle, everyone stayed well clear of the walls in opening practice.
Jenson Button paced the opening session © LAT
The session was fought out between the McLarens and Michael Schumacher, with Jenson Button coming out on top and the Mercedes pushing Lewis Hamilton back to third. Nico Rosberg put the second Mercedes fourth as Red Bull started off with fifth for Sebastian Vettel and a low-key 14th for a still content Mark Webber.
Williams got both cars in the top 10, just behind an encouraging eighth place for Tonio Liuzzi. His Force India team-mate Adrian Sutil lost mileage to technical problems, as did Jarno Trulli at Lotus - though not as much as Virgin's Lucas di Grassi, who failed to set a time due to an "assembly error" with his brake.