The Brit topped the timesheet, clocking a 1m31.358 on the Soft compound Pirelli tyre late in the afternoon.
“Today was tricky with it being so hot and very gusty but we still managed to get through plenty of work,” Hamilton said.
“Our focus was on advancing our understanding of the tyres and also the rear of the car so that we can improve our long runs – particularly during the race and on the SuperSoft compound.
“We came here with a specific goal, so it was positive to get on top of that with the team.”
While his team seeks to improve its tyre troubles, Hamilton is forecasting different tyre management in Russia next week, on a track which doesn’t compare to Bahrain in terms of degradation.
“Sochi is a smoother track and less abrasive on the tyres, so they can go quite a long way. Hopefully we can rely on the pace of our car there rather than our use of the tyres.”
Valtteri Bottas will take the wheel of the W08 Wednesday for the second and final day of the test.