Valencia MotoGP: Marquez leads Pramac pair in disrupted FP1
Reigning MotoGP champion Marc Marquez was fastest in the opening practice at Valencia, which was red-flagged early on due to weather conditions.
The session started under soaking wet track conditions, which are forecast for the whole of the final weekend of the campaign.
The red flag came out just seven minutes and 12 seconds into FP1, soon after Alex Rins impressively but narrowly avoided a crash at Turn 13 and Maverick Vinales ran through a huge puddle at the exit of T14.
It took nearly 30 minutes for the rain to ease off and the session to be restarted, and the pace rapidly improved in the first half of FP1.
Marquez dominated the proceedings by improving numerous times and leading by over a second but when he pitted the field quickly caught up and Danilo Petrucci demoted him to second with a 1m40.479s.
But when Marquez returned to the track he set a 1m39.787s in just two laps, a time that was not matched by the rest of the field.
Jack Miller quickly closed the gap to just 0.086s and he looked set to improve further with just two minutes on the clock, only for the Australian to crash at Turn 10.
Marquez then lowered his benchmark by another two hundredths of a second after the chequered flag fell to increase his gap over Miller to 0.106s.
Miller's Pramac Ducati teammate Petrucci took third, with the Italian's future factory teammate Andrea Dovizioso completing the top four.
Dani Pedrosa kicked off his farewell weekend in fifth, followed by Andrea Iannone and Maverick Vinales, the Yamaha rider ending up more than a second off the pace.
Ducati wildcard Michele Pirro was eighth as KTM's Pol Espargaro and Suzuki's Alex Rins completed the top 10.
Valentino Rossi had an off-track moment at Turn 8 and was in the end only 12th ahead of fellow Yamaha rider Johann Zarco.
Stefan Bradl, who is replacing the injured Cal Crutchlow at LCR Honda, was 16th, while the recovering Jorge Lorenzo took 19th.
Along with Miller, fellow Ducati privateers Alvaro Bautista and Xavier Simeon also crashed in the dying stages of the practice.
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