Charles Leclerc topped the second practice session for the Bahrain Grand Prix at Sepang on Friday, putting Ferrari at the front as high track temperatures, tyre degradation and traffic made the circuit difficult to master.
Leclerc was followed by Isack Hadjar, with Lando Norris third and Lewis Hamilton fifth as Ferrari and McLaren showed stronger pace than in the opening session.
Max Verstappen, who topped FP1 for Red Bull, was notably quieter in the second session after running just one set of tyres. The reason for his limited running was unclear.
McLaren improved significantly from FP1, with Norris climbing to third while Oscar Piastri finished sixth.
Mercedes also had a difficult session, with George Russell and Kimi Antonelli both making mistakes on their flying laps on the soft tyres.
Liam Lawson and Pierre Gasly completed the midfield presence in the top 10.
The conditions also made tyre management a major talking point. High track temperatures meant the soft tyres were struggling to deliver more than one strong push lap before performance dropped away.
Traffic was another issue, with drivers having to fight for track position while it remained unclear how useful the tow would be around the Sepang circuit.
The final corner proved particularly tricky, with drivers who strayed from the racing line quickly picking up marbles and losing grip.
The session also ended with a problem for Gabriel Bortoleto, who stopped on track with a suspected gearbox issue. Audi was expected to provide further information on the failure.
With mistakes easy to make and tyres offering little margin for another push lap, qualifying on Saturday could come down to who can find a clean lap without overheating or compromising their tyres.
