The final practice session for the premier class started with some wind and ended with some smoke, but neither of those slowed down Pol Espargaro, nor did an early crash at turn 5. The Spaniard showed some good consistency as he robbed colleague Miguel Oliveira from topping another session on home soil. Oliveira ended second by only three hundredths of a second after putting together a solid session and the home rider was only six thousandths faster than Takaaki Nakagami. However, the Japanese rider had a more eventful afternoon, topping the session early on before another crash at turn 4, which dropped him to third. Nakagami missed out on the final 7 minutes of the session as the rider looked in a bit of pain and the team had a big repair job scheduled.
Maverick Vinales continued to be the happiest Yamaha in Portugal, the Spaniard fourth fastest ahead of Aleix Espargaro, both within a tenth of a second of top spot. Alex Marquez made a slow start to his weekend but climbed into sixth in FP4, ahead of the Petronas duo of Fabio Quartararo and Franco Morbidelli, with Brad Binder and Stefan Bradl rounding out the top 10.
Joan Mir was the only rider to be tempted by the medium rear tyre and the world champion persisted with the choice, leaving him 12th on the timesheets, ahead of Andrea Dovizioso and Johann Zarco as the best Ducatis in the session. However, Zarco’s machine wasn’t exactly on its best behaviour, starting to pour smoke in the final minute of the session. After showing good speed over the weekend, Jack Miller was down in an unusual 15th position, seven tenths down on the top time.