With the circuit offering up more grip on Saturday morning following Friday’s inaugural day of action around the Algarve circuit, Miller struck to the front of the field in the closing stages with a 1m 39.205secs aboard the Pramac Ducati.
Local hero Miguel Oliveira continued to give the socially distanced fans something to cheer about at home with a strong run to second position on the Tech 3 KTM, the Portuguese rider coming into his local round with his eyes firmly set on a maiden pole position tilt.
After hurting his hand in a fall during FP2, Takaaki Nakagami showed no ill effects from in FP3 as to head up the Honda challenge in fifth position, ahead of Friday pace setter Johann Zarco, his countryman Fabio Quartararo and Pol Espargaro on the factory KTM.
Rounding out the top ten with a passage straight through to Q2 was Maverick Vinales and – for the first time in what has been an unexpected full season in MotoGP – Stefan Bradl, the German impressing on the Repsol Honda.
By contrast, the likes of Morbidelli and new champion Mir would be heading straight for Q1, the leading pair in the overall standings set to go up against the likes Aleix Espargaro (12th), Brad Binder (13th), Cal Crutchlow (14th) and Valentino Rossi (20th)