LE MANS - Defending world champion Jorge Lorenzo celebrated his birthday in style by dominating opening practice for Sunday's French Grand Prix while Yamaha teammate Valentino Rossi struggled in 10th place.

Lorenzo, who turned 29 on Wednesday, clocked 1min 32.830sec with Italy's Andrea Iannone 0.339sec behind on a Ducati while the world champion's Spanish compatriot Marc Marquez, on a Honda, was third fastest, 0.483sec off the pace. Lorenzo won the season opener in Qatar before current series leader Marquez stormed to victory in Argentina and the United States.

Rossi, the nine-time world champion, won last time out in Spain but endured a miserable practice session on Friday, finishing in 10th at 1.144sec off Lorenzo. "I am very satisfied because from the beginning we started with a good setting and I was relatively fast, quite comfortably," said Lorenzo, who won at Le Mans in 2009, 2010, 2012 and last year. "In the afternoon we improved the bike a little bit and we went even faster with quite a big difference, a couple of tenths, to the rider in second place.  "It wasn't just one lap, we also had a good pace so it was a very good start to the weekend. Let's see if tomorrow we can increase the pace a little bit more and prepare for the race to our best capabilities."

Marquez, a winner in France in 2014, has a 17-point lead over Lorenzo in the championship and admitted Friday had been a tough test for him and Honda teammate Dani Pedrosa who was eighth fastest overall. "Today was demanding. We knew this circuit would cause us to struggle a bit, but we're overcoming things fairly well," said two-time world champion Marquez.

"I have a good pace and I'm feeling good, although we're losing some time on both of this circuit's hard acceleration points; it's something that's difficult to recover from afterwards." Rossi was left to bemoan both sessions where he was constantly struggling on a track where his last victory was eight years ago.

"We tried a lot of different things for the setting because this morning I wasn't fast enough, but unfortunately in the afternoon the situation was worse and we didn't find the right way," said the Italian. "In fact, in the morning I was also quite slow and for this reason I didn't try the third tyre from Michelin, because we didn't have time. I will try it tomorrow morning."

French Grand Prix practice times:

MotoGP: 1. Jorge Lorenzo (ESP/Yamaha) 1min 32.830sec, 2. Andrea Iannone (ITA/Ducati) at 0.339sec, 3. Marc Marquez (ESP/Honda) 0.483, 4. Pol Espargaro (ESP/Yamaha Tech3) 0.576, 5. Andrea Dovizioso (ITA/Ducati) 0.744, 6. Aleix Espargaro (ESP/Suzuki) 0.765, 7. Maverick Vinales (ESP/Suzuki) 0.783, 8. Dani Pedrosa (ESP/Honda) 0.918, 9. Hector Barbera (ESP/Ducati Avintia) 1.121, 10. Valentino Rossi (ITA/Yamaha) 1.144, 11. Danilo Petrucci (ITA/Ducati Pramac) 1.220, 12. Cal Crutchlow (GBR/Honda LCR) 1.223

Moto2: 1. Johann Zarco (FRA/Kalex) 1:37.370, 2. Tom Lüthi (SUI/Kalex) at 0.065, 3. Jonas Folger (GER/Kalex) 0.187, 4. Lorenzo Baldassarri (ITA/Kalex) 0.488, 5. Alex Rins (ESP/Kalex) 0.587

Moto3: 1. Brad Binder (RSA/KTM) 1.43.365, 2. Romano Fenati (ITA/KTM) at 0.076, 3. Jules Danilo (FRA/Honda) 0.160, 4. Jorge Navarro (ESP/Honda) 0.192, 5. Nicolo Bulega (ITA/KTM) 0.373