Dani Pedrosa continued the momentum from his Jerez victory by leading first practice for the French MotoGP at Le Mans.
Riding in cold but bright conditions, the Repsol Honda star set a best lap time just 0.040s ahead of Jorge Lorenzo, whose Yamaha team-mate Valentino Rossi
also got off to a strong start in third (+0.293s).
As they had hoped, Ducati team-mates Nicky Hayden
and Andrea Dovizioso
found the hard-braking circuit characteristics to work in the Desmosedici's favour and were four and fifth fastest, both within half-a-second of Pedrosa.
Top satellite rider in the standings Cal Crutchlow, riding for the local Tech 3 Yamaha team, completed the top six with rookie star Marc Marquez seventh – and only 0.525s from team-mate Pedrosa.
Le Mans is the first circuit since the opening round in Qatar that Marquez has not previously tested his RC213V at.
Eighth place went to Gresini Honda's Alvaro Bautista, with LCR Honda's Stefan Bradl in ninth (+0.833s). Hector Barbra put his recent domestic troubles aside and was the top CRT rider in tenth place for Avintia Blusens, 1.3s from Pedrosa.
With rain an almost constant threat at Le Mans, riders pushed harder than normal for a lap time in FP1 - only the top ten after third free practice are granted automatic access to the final part of the new qualifying format.
Pedrosa's best lap of 1m 34.645s was within one-second of his own race lap record.
Marquez starts this weekend with a three point lead over Pedrosa. Lorenzo is just four points from the top, having lost out on second place at Jerez due to a dramatic last turn pass by Marquez. Each of the trio have taken one win so far this year.
Crutchlow's rookie team-mate Bradley Smith ran off at high speed through the sweeping first turn early in the session, but kept control as he bounced through the gravel and went on to finish in 15th.
Pramac Ducati's Ben Spies is missing his second event in a row to undergo further rehabilitation on his healing shoulder.
The Texan is being replaced by Ducati test rider Michele Pirro, who was 13th quickest - two places behind team-mate Andrea Iannone, riding sore after recent arm pump surgery.
Randy de Puniet, the only French rider on the grid, finished between Pirro and Smith in 14th place for Aspar.
Second practice takes place this afternoon.Free practice (1):
1. Dani Pedrosa
2. Jorge Lorenzo
3. Valentino Rossi
4. Nicky Hayden
5. Andrea Dovizioso
6. Cal Crutchlow
7. Marc Marquez
8. Alvaro Bautista
9. Stefan Bradl
10. Hector Barbera
11. Aleix Espargaro
12. Andrea Iannone
13. Michele Pirro
14. Randy De Puniet
15. Bradley Smith
16. Hiroshi Aoyama
17. Claudio Corti
18. Colin Edwards
19. Yonny Hernandez
20. Danilo Petrucci
21. Karel Abraham
22. Bryan Staring
23. Michael Laverty
24. Lukas Pesek