Lewis Hamilton fastest in first Baku Formula 1 practice session

Hamilton was fastest in spite of Rosberg being quicker in the final sector and equal in the second, but the world champion had to sit out the last part of the session after brushing the wall and flat-spotting his tyres.

Hamilton, who claimed to have done no Baku preparation on the simulator, led for most of the first half hour until Valtteri Bottas went half a second faster with a 1m47.707s.

The Williams programme then suffered a brief interruption as Bottas reported smoke in the cockpit and made for the pits.

Bottas had set his time with an opportune tow down the long main straight, on which the cars reach just over 200mph, but even so when he returned to action later on he bettered it with a 1m47.096s.

Esteban Gutierrez was the first F1 driver to overshoot at Turn 15 and explore the run-off area, discovering - as with several runners in the earlier GP2 session - that getting out again requires a precisely executed spin-turn or a fiddly multi-point shuffle.

Later in the session the Mercedes drivers were first to fit the super-soft Pirelli tyres, and Rosberg edged out Bottas with a 1m46.812s.

But Hamilton then outpaced him by 0.377s before tapping the outside wall at Turn 3 and flat-spotting his tyres as he tried to avoid becoming snagged in the controversially tight run-off area there.

There was encouragement for McLaren as Fernando Alonso went fourth fastest, albeit 1.554s off Hamilton's quickest lap - but Alonso, like Bottas, set his time on softs rather than super-softs.

Sebastian Vettel, Sergio Perez, Jenson Button and Felipe Massa might appear some way off but they, too, were running on softs.

Ninth-fastest Carlos Sainz Jr made a late run on super-softs but he deranged his front wing at Turn 15 on his best lap.

Red Bull endured a troubled session as Max Verstappen sat out the majority, completing just three timed laps before pitting to have a suspected oil leak investigated.

Daniel Ricciardo brought out the red flags for an 11-minute stoppage after he collected the Tecpro barrier at the exit of Turn 15 and lost a rear wheel, along with his wing.

PRACTICE ONE TIMES