Having seen his championship lead slashed last time out at Brno, Nico Terol kick-started his Indianapolis weekend in perfect fashion with the fastest time during Friday's 125 practice sessions at the Brickyard.

Terol's best time in the second session of the day was easily the quickest of the day as lap-times tumbled in FP2, with riders becoming more accustomed to the new track surface which had been criticised by MotoGP riders following their morning session over a lack of grip.

Terol was towards the top of the times throughout the session but was the only rider to dip below the 1m 50s mark, eventually ending up more than three quarters of a second clear of Johann Zarco - the man closest to him in the standings - in second.

Worryingly for his championship rival, Terol's best lap of the session came without the benefit of a tow from another rider on the long run out of the final corner to the start/finish line.

Alberto Moncayo, fresh from his maiden podium last time out in the Czech Republic, slotted into third place late on in the session and he was only 0.001s down on Zarco. Sergio Gadea was the final rider within a second of the benchmark time in fourth place for the Paris Hilton Aprilia team.

Efren Vazquez was fifth fastest ahead of Brno winner Sandro Cortese, with Hector Faubel and Jonas Folger completing the top eight - the latter returning to action this weekend after illness forced him to sit out the Czech weekend.

Friday practice (2):
1. Terol (Aprilia) 1m 49.381s
2. Zarco (Derbi) +0.774s
3. Moncayo (Aprilia) +0.775s
4. Gadea (Aprilia) +0.937s
5. Vazquez (Derbi) +1.197s
6. Cortese (Aprilia) +1.391s
7. Faubel (Aprilia) +1.667s
8. Folger (Aprilia) +1.728s
9. Viales (Aprilia) +1.762s
10. Kent (Aprilia) +2.008s

11. Webb (Mahindra) +2.177s
24. Stafford (Aprilia) +5.013s
25. Mackenzie (Aprilia) +5.118s