Jack Miller topped the timesheets in opening practice as the French MotoGP weekend began under a dark cloud.

The world of motor racing was left reeling from the shocking news of Nicky Hayden's cycling crash that has left the former MotoGP Champion in a critical condition in hospital.

While the thoughts of all in the paddock were with the American, the show had to go on, starting with Friday's first practice.

On a wet and cold Le Mans circuit, Miller set the early pace before Jorge Lorenzo and then Maverick Vinales took over at the front.

Midway through the session, championship leader Valentino Rossi was down in 17th place, Vinales was leading, and Marc Marquez was P13.

As the track conditions improved, Marquez went quickest with a time of 1:41.837, but that was obliterated by Miller's 1:38.204. The Marc VDS leapt up the order when he swapped his wets for slicks.

That prompted others to make the switch. Marquez put in a late improvement to close the gap to 1.2s while Johann Zarco, with a new Tech 3 Yamaha deal in the bag, was third.

Rossi finished P8 with Vinales falling to 10th.

Times:

1 Jack MILLER EG 0,0 Marc VDS 1'37.467

2 Marc MARQUEZ Repsol Honda Team 1'38.755 1.288

3 Johann ZARCO Monster Yamaha Tech 3 1'39.248 1.781

4 Cal CRUTCHLOW LCR Honda 1'39.607 2.140

5 Loris BAZ Reale Avintia Racing 1'40.427 2.960

6 Karel ABRAHAM Pull&Bear Aspar Team 1'40.528 3.061

7 Bradley SMITH Red Bull KTM Factory Racing 1'40.817 3.350

8 Valentino ROSSI Movistar Yamaha MotoGP 1'40.894 3.427

9 Alvaro BAUTISTA Pull&Bear Aspar Team 1'41.024 3.557

10 Maverick VIÑALES Movistar Yamaha MotoGP 1'41.307 3.840

11 Andrea IANNONE Team SUZUKI ECSTAR 1'41.562 4.095

12 Jonas FOLGER Monster Yamaha Tech 3 1'41.644 4.177

13 Dani PEDROSA Repsol Honda Team 1'41.854 4.387

14 Andrea DOVIZIOSO Ducati Team 1'41.871 4.404

15 Danilo PETRUCCI OCTO Pramac Racing 1'41.887 4.4206

16 Jorge LORENZO Ducati Team 1'41.947 4.480

17 Scott REDDING OCTO Pramac Racing 1'42.040 4.573

18 Tito RABAT EG 0,0 Marc VDS 1'42.094 4.627

19 Sam LOWES Aprilia Racing Team Gresini 1'42.243 4.776

20 Sylvain GUINTOLI Team SUZUKI ECSTAR 1'42.891 5.424

21 Hector BARBERA Reale Avintia Racing 1'42.953 5.486

22 Aleix ESPARGARO Aprilia Racing Team Gresini 1'43.114 5.647

23 Pol ESPARGARO Red Bull KTM Factory Racing 1'43.519 6.052