Vinales up to second with the second lap of his first time attack. Ogura was improving too but lost out in the final sector and drops to seventh with Vinales' improvement.
Good laps for Ogura and Vinales - 6th and 8th respectively.
Joan Mir was on a PB but he blew the final corner and doesn't improve.
Luca Marini's soft tyre time attack has resulted only in 15th.
Fabio Quartararo just crosssed the line looking not-too-stoked with his M1. He's still fastest for now, though.
Crash for Brad Binder at turn nine. He's walking away.
That didn't last long for KTM, as Fabio Quartararo returns to the top, ahead now of Marc Marquez who just did a 1:36.973 on a 14-lap-old medium rear which is rather alarming.
Half-an-hour to go and an early time attack from Johann Zarco - briefly fastest for the Frenchman, but he's bumped back to third by Binder and Acosta, who now leads a KTM 1-2.
Joan Mir pops in a personal best for the session with a 1:37.414 on a 10-lap-old medium rear tyre.
Bagnaia, in comparison, is running 1:37.6s in his last couple of laps on medium rear tyre that is now 6-laps-old.
Better that time by for Bagnaia - 1:37.096 moves him to second place in the session, 0.025s behind Quartararo.
Mistake at turn two for Bagnaia would explain his poor last lap, but he's not improving on this current lap either after three sectors. He crosses the line with a 37.677.
Bagnaia now out on a fresh medium rear tyre. HIs most recent lap was a 1:38.7, which won't cut it. We'll see how this run develops for the three-time winner here.
Firmly in the 'race pace' portion of this session with 41 minutes to go.
Brad Binder circulating on used medium tyres and even just on the TV pictures the lack of rear grip seems evident.
Bagnaia currently in P10. He was last out on a used soft tyre, which presumably was for a Sprint simulation.
Quartararo to the top on a 1:37.071, and Acosta moves up to fifth.
Acosta now on a fresh medium front & fresh soft rear tyre. Most still on medium rears, either new or used.
Strong early part of the resart from Franco Morbidelli who jumps up to third place. Acosta into the top-10 too in ninth.
Pit lane is open once again and we are back underway for the final 51:35 of this PR session.
Pit lane will re-open at 15:22.
Looks like the air fence is almost fixed now at turn five, so hopefully not too much longer to get this PR session resumed.
51:35 on the clock when this gets back underway. Still waiting for a restart time to be announced, but the air fence is still being re-deployed.
Confirmation on the TV world feed that the red flag is to replace the air fence on the outside of turn five.
TV replays showing Marquez walking away, and he doesn't seem to be favouring anything. He was definitely uncomfortable immediately afterwards, possibly only winded. He's on a scooter now and getting back to the pits.
Red flag now for the Marquez crash, possibly for the air fence on the outside of turn five.
Joan Mir up to third place with his latest lap on the Honda.
And it's a crash for Alex Marquez, his second of the day. Turn five for the Gresini rider and he looks hurt.
Alex Marquez to the top now on a 1:37.242. Marc just under a tenth slower early on in second place.
First lap times coming in now and it's Raul Fernandez fastest at the start of PR with a 1:37.778.
We have a green light at the end of pit lane and we are underway for an hour of MotoGP Practice in Jerez.