Sebastian Vettel has ended the morning session from day two, test two in Barcelona on the top of the timesheets.
The German set a 1:16.841 with the C5 compound to clear the rest of the field by just under three-tenths of a second.
However, it wasn't a smooth sailing morning for the four-time world champion, as a spin at Turn 5 saw him take a trip into the gravel, which caused a red flag.
He managed to get the car back to the pit lane on his own, unlike Max Verstappen who spun at the same corner, beaching the RB16 in the gravel.
The day started slowly as a damp track made teams reluctant to set many laps until the circuit dried up.
Bottas also found himself in the gravel at Turn 5 moments before Verstappen spun off as he corrected oversteer. However, he never found himself facing the wrong way and continued back to the pits.
Bahrain International Circuit - Winter testing