Hector Barbera led Friday practice for the 250cc Australian Grand Prix at Phillip Island, despite being carried off-track on a stretcher with 16 minutes to go.

The double 2009 race winner suffered a slow but painful highside from his Pepe World Aprilia while fastest, but still finished the session on top by 0.573sec.

A topsy-turvy classification saw Scot Honda's Raffaele de Rosa closest to Barbera, with Frenchman Jules Cluzel third and reigning 125cc world champion Mike di Meglio fourth.

The world championship contenders all made a slow start to the weekend with title leader Hiroshi Aoyama - who holds a 26 point lead over Alvaro Bautista and 28 point lead over Marco Simoncelli - only eleventh fastest. Bautista was twelfth and Simoncelli tenth.

The session began with a brief rain shower, but the fickle Phillip Island weather was soon bright and sunny again, causing little reduction in track time.

Friday practice - Phillip Island:

1. Barbera (Aprilia)
2. de Rosa (Honda) +0.573sec
3. Cluzel (Aprilia) +0.589sec
4. di Meglio (Aprilia) +0.675sec
5. Faubel (Honda) +0.747sec
6. Pasini (Aprilia) +0.781sec
7. Wilairot (Honda) +0.794sec
8. Debon (Aprilia) +0.812sec
9. Abraham (Aprilia) +0.881sec
10. Simoncelli (Gilera) +0.980sec