F1 Spanish GP FP2: Lewis Hamilton fastest from Sebastian Vettel

The reigning world champion clocked a 1m26.852s on the medium-compound Pirelli tyre, 0.408s clear of Ferrari's Sebastian Vettel.

Nico Rosberg, who was quickest in first practice, had downshifting problems on his qualifying-simulation run and ended up 0.764s adrift of his team-mate in third.

Hamilton also set the pace on the hard tyres early in the session, the Briton 1.249s clear of Rosberg, with Vettel 0.010s adrift.

Track temperatures hit 50C and ambient temperatures 29C on a glorious day at Barcelona's Circuit de Catalunya, with conditions expected to get warmer over the course of the weekend.

When the teams switched focus to high-fuel long runs, several drivers reported a lack of grip and were warned about a crosswind at Turn 3.

Aside from a small lock-up on his medium-tyre run, Hamilton didn't put a foot wrong with Mercedes looking like it still holds an advantage over rival Ferrari.

Ferrari's Kimi Raikkonen was fourth quickest, the Finn securing his best time on the second lap of his run after a small mistake on the first.

While Daniil Kvyat set fifth fastest time, one second off the pace, his Red Bull team-mate Daniel Ricciardo didn't fair so well.

Having completed just nine laps in first practice, the Australian didn't make an appearance in the second until the five minutes before the end because the team changed his engine.

Red Bull had run a power unit with higher mileage in the first session before swapping to what will be Ricciardo's fourth of the season and he ended up 13th.

Toro Rosso's Max Verstappen was just 1.165s slower than Hamilton in sixth, with Jenson Button in the new-liveried and upgraded McLaren half a second further back in seventh.

Valtteri Bottas was the leading Williams in eighth, ahead of Toro Rosso's Carlos Sainz Jr, with the other Williams of Felipe Massa completing the top 10.

McLaren's Fernando Alonso was 11th ahead of Romain Grosjean, who brought out the red flag when his Lotus' engine cover broke off on the pit straight.

After spending nearly an hour in the garage, Grosjean emerged to run the medium tyres to finish 12th, 2.2s off the pace and two places clear of team-mate Pastor Maldonado.

The Saubers of Felipe Nasr and Marcus Ericsson were 15th and 16th ahead of Force India's Nico Hulkenberg and Sergio Perez, with Will Stevens and Roberto Merhi propping up the timesheets in the Manor-run Marussias.

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