The MotoGP rookie, who has a sensational record of three pole positions and three podiums from his first three races - including a debut win last time out in Estoril - sustained damage to both ankles after being flung high in the air from his Fiat Yamaha as he switched direction from right to left.

The 20-year-old Spaniard, who recently underwent surgery for arm pump, went through a full 360-degree flip before slamming into the ground and is currently having his injuries examined in a nearby hospital. Lorenzo will not ride during this afternoon's second free practice session.

Lorenzo's team-mate Valentino Rossi set the pace in free practice (1), with Ducati's world champion Casey Stoner 0.4secs slower in second and Dani Pedrosa - currently tied with Lorenzo at the top of the standings - almost one second from the #46 in third.

More to follow...