It was a bright but chilly start in Barcelona for the premier class and Fabio Quartararo felt at home at the top of the standings throughout the first practice session. The Frenchman finished morning practice over four tenths of a second ahead of championship leader Andrea Dovizioso, who had a slow start but then got up to speed to climb into second. Despite an uncharacteristic tumble at turn five halfway through proceedings, Joan Mir recovered to finish third, marginally ahead of recent victor Maverick Vinales.
Aleix Espargaro joined the top five on home soil, just a touch quicker than Franco Morbidelli and with Alex Rins in seventh position as the last man to post a time within a second of the leader. Valentino Rossi added a fourth Yamaha to the top eight, while the continuously convalescent Cal Crutchlow returned to action with a solid ninth position and top Honda in the session. Miguel Oliveira took the final place in the top ten as top KTM, but with less than a tenth keeping him ahead of Takaaki Nakagami, Johann Zarco, Iker Lecuona and Bradley Smith.
Pecco Bagnaia in 15th and Pol Espargaro in 16th place had a low-key start in Montmelo, much like Jack Miller in 18th and Brad Binder 21st, although not everyone was tempted by a late time attack.