Joan Mir has also been ruled out of next week's Japanese MotoGP at Motegi.
Fast crash for the Italian as he loses the front.
More frustration for Maverick Vinales as he fails to get his Aprilia stopped for turn one.
Quartararo is losing close to four tenths every lap in the final sector. That's a huge margin that could play a big role in qualifying.
Marco Bezzecchi, who has also been very quick this weekend, has gone second - +0.010s off Oliveira.
KTM's impressive day is continuing as Miguel Oliveira currently leads the way from Quartararo.
There are a lot of hard front tyres being used - Marquez is on a used tyre with Quartararo on a new hard front. Medium appears to be the rear tyre of choice for tomorrow's race at this stage for most.
We're underway with Aragon MotoGP FP4.
Moto3 Qualifying - CLICK HERE for the full results
Breaking news: Joan Mir has withdrawn from the Aragon MotoGP due to injury.
Out of the top ten in FP3, Aleix Espargaro needs a big FP4 and Qualifying session at Aragon.
A miraculous 'save', followed by a turn seven crash and end-of-session stoppie - it's already been an eventful Saturday for Marquez.
Fastest in FP3, here's Miller at Aragon.
Good afternoon and welcome back to qualifying day at the Aragon MotoGP. Coming up shortly is FP4.
Moto2 FP3 - CLICK HERE for the full results
MotoGP FP3 - CLICK HERE for the full results
Aleix Espargaro, Maverick Vinales and Marc Marquez have all missed out on the top ten. Miller finishes fastest from Bagnaia.
Rins has also crashes in sector one.
Darryn Binder and Cal Crutchlow have both suffered late crashes.
Brad Binder has just crashed at turn two.
Binder improves again as team-mate Miguel Oliveira goes third fastest - what a morning for KTM.
The final time attacks have now begun.
Great lap by Brad Binder as he moves into second place for KTM.
Quartararo has reduced Miller's advantage to just over two tenths.
Wow! Miller sets the first sub 1m 47s lap of the weekend.