Enea Bastianini has headed up an all-Ducati top four in Friday practice for the San Marino MotoGP round, in which factory team rider Francesco Bagnaia incurred a grid penalty.

Bagnaia will start three positions back from where he qualifies as punishment for riding slowly on the racing line late in Free Practice 1, causing an obstruction to Alex Marquez (Castrol LCR Honda) and Bastianini (Gresini Racing) through Turns 2 and 3 of the Misano circuit.

The latter would go on to set the fastest lap of the day in Free Practice 2, a 1:31.517s which was 0.114s up on Bagnaia’s best and 0.185s on that of the other Ducati Lenovo Team rider, Jack Miller.

Pramac Racing’s Johann Zarco was fourth and championship leader Fabio Quartararo fifth on his Monster Energy Yamaha at 0.326s off the pace.

Quartararo had topped Free Practice 1 on a 1:32.313s despite a number of moments running wide through the fast Curvone sweeper, but all 25 riders set their fastest laps in the latter session of the day.

In what was a tumultuous day for Bagnaia, who has won the last three races of the season, he crashed less than a quarter of an hour into FP2 at Turn 13.

The Italian was able to regroup and eventually go quickest with less than a minute to go on a 1:31.631s, but he would hold first spot for barely more than a second as countryman, stablemate, and future team-mate Bastianini followed him across the line to clock a 1:31.517s.

Behind Miller, Zarco, and Quartararo on the timesheet was Aprilia Racing duo Maverick Viñales and Aleix Espargaro, then Jorge Martin (Pramac Ducati), Marco Bezzecchi (Mooney VR46 Ducati), and Franco Morbidelli (Monster Energy Yamaha).

Zarco and Alex Rins (Suzuki Ecstar) also crashed in the session, the latter ending up 14th at 0.848s off the pace.

Saturday sees Free Practice 3 at 17:55 AEST, Free Practice 4 at 21:30, Qualifying 1 at 22:10, and Qualifying 2 at 22:35.

Friday practice: San Marino MotoGP Combined times