Czech GP winner and FIM MotoGP Championship leader Marc Marquez (Repsol Honda Team) had three bikes at his disposal for the Brno Test.
The seven-time champion also tried a new Honda aero package on one of the RC213Vs, but he did most of his work on his standard bike and as he completed 70 laps, finishing eighth on the timesheets...likely not pushing too hard on test duty.
Team Suzuki Ecstar's Alex Rins worked with the new aero package which we saw across the weekend, but he also had a small evolution on the chassis and swingarm that he tested in Barcelona.
The Spaniard finished fourth fastest having completed 69 laps at Brno, with Suzuki team-mate Joan Mir also completing 69 laps - some while using the aero package for the first time - before his crash saw him end the test in seventh.
Yamaha new version
One of the key talking points leading up to the Brno Test was Yamaha rolling out a first version of next year's bike.
Rossi was out on a blacked-out YZR-M1 early in the day as he and team-mate Viñales got their first taste of what the 2020 bike will be like, and the duo had a new seat unit to test for their 2019 bikes.
They were out on track until the chequered flag was waved as ‘The Doctor' shot up to P6 on his final run, with 63 laps completed by the nine-time champion. Vinales got 74 laps under his belt ahead of Austria.
In the Petronas Yamaha SRT box, pacesetter Quartararo tested carbon forks on his M1, the same as the factory team use.