Ducati rider Andrea Dovizioso set the pace in an incident-filled opening day of the final MotoGP pre-season test in Qatar.
The third and last winter test ahead of the 2017 MotoGP season started with Dovizioso putting in the quickest time at the Losail circuit.
His 1:54.818 was set with just over two hours of the day remaining, demoting his new Ducati team-mate Jorge Lorenzo to second.
However, Lorenzo did not stay in the runner-up spot, falling to fifth place by the end of the session.
Yamaha's Maverick Vinales improved late on to claim second, 0.361s adrift of Dovizioso’s benchmark.
LCR Honda’s Cal Crutchlow and Aspar’s Karel Abraham moved up to third and fourth in the final hour.
Tech3 Yamaha’s Jonas Folger was sixth, ahead of works rider Valentino Rossi and Honda’s Dani Pedrosa.
Reigning champion Marc Marquez finished down in 12th after two crashes. The first fall happened mid-way through the session after emerging on track with Honda’s new fairing.
He then crashed at Turn 2 in the last hour of running, while former Moto2 racers Alex Rins and Sam Lowes also suffered accidents.
They were not the only ones, though, with Pol Espargaro, Andrea Iannone and Aleix Espargaro also falling during the test session.