Alex Marquez led his brother Marc on the opening day of MotoGP's final pre-season test in Thailand, despite two crashes for Marc.

The elder Marquez had a fairly sudden fall at the final corner while on his first flying lap, then fell again - albeit much more gently - at Turn 5 shortly afterwards.

Ducati, which is still finalising its aero package for the start of the season and testing different configurations, acknowledged that his confidence had been shaken by such a start. But Marquez sped up by the end of the day, finishing a tenth behind his brother - arguably the standout rider of the pre-season so far.

Behind a Franco Morbidelli-propped up Ducati 1-2-3, Marco Bezzecchi was the lead Aprilia in fourth, with the lead Honda 0.005s back (Johann Zarco) and the lead KTM 0.078s back (Maverick Vinales).

Jack Miller set the best time by a V4 Yamaha bike in the morning session (which featured a Pecco Bagnaia-Jorge Martin 1-2), which ended up 1.063s off, while stablemate Fabio Quartararo caused a bit of a stir by showing his bike a middle finger after an on-track moment.

"As I said before, the rider cannot wait," team manager Massimo Meregalli told MotoGP.com when asked about this. "But we know, we knew since the beginning, that we couldn't expect magic. Since the beginning we were aware that, especially in the beginning for us, it was going to be really a learning process.

"I want to believe, and I'm still thinking, that from the second part of the season gradually we will improve the performance."

Day 1 results

1 Alex Marquez (Ducati) 1m29.262s
2 Marc Marquez (Ducati) +0.129s
3 Franco Morbidelli (Ducati) +0.189s
4 Marco Bezzecchi (Aprilia) +0.200s
5 Johann Zarco (Honda) +0.205s
6 Raul Fernandez (Aprilia) +0.224s
7 Joan Mir (Honda) +0.232s
8 Maverick Vinales (KTM) +0.278s
9 Fabio Di Giannantonio (Ducati) +0.381s
10 Brad Binder (KTM) +0.495s
11 Luca Marini (Honda) +0.512s
12 Pecco Bagnaia (Ducati) +0.536s
13 Pedro Acosta (KTM) +0.588s
14 Ai Ogura (Aprilia) +0.690s
15 Jorge Martin (Aprilia) +0.844s
16 Enea Bastianini (KTM) +0.891s
17 Jack Miller (Yamaha) +1.063s
18 Fabio Quartararo (Yamaha) +1.245s
19 Alex Rins (Yamaha) +1.250s
20 Diogo Moreira (Honda) +1.691s
21 Toprak Razgatlioglu (Yamaha) +2.312s
22 Michele Pirro (Ducati) +3.348s