The Kawasaki rider set a blistering fastest lap of 1:41:430 to start at the front of the grid ahead of two Aprilias.
Eugene Laverty and Lorenzo Savadori were second and third fastest respectively, with Alex Lowes fourth on the grid.
Portugal
Davies crash all but hands title to Rea
17/09/2017 AT 14:46
The session had faced delays after a horrible crash involving Tom Sykes in free practice earlier in the morning.
Sykes escaped with relatively minor injuries, but the strength of the medication required to treat a broken finger and forearm burn ruled him out of the remainder of the weekend.

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Portugal
Tom Sykes admits he is 'a very lucky man' after horror crash
16/09/2017 AT 14:05
Superbikes
Jonathan Rea Q&A - On first memory on a bike, best win, bigges setback and more
16/06/2022 AT 09:12