Antonelli tops FP2 as Gasly crashes heavily at Spa

Alpine's Pierre Gasly caused a red flag with a heavy crash in Friday practice at the Belgian Grand Prix as Mercedes' Kimi Antonelli set out his stall for the weekend with the fastest time.

Gasly lost control on the exit of the Fagnes medium-speed chicane in the middle sector and clipped the barrier, tearing off his right rear wheel.

The incident cut short the race-simulation runs in the final part of the session and will lead to a long night for Gasly's team.

The Frenchman said: "Overall it was a good day of testing. Just need to work on what happened in the P2.

"I just had a big snap, lost the car, but it was a huge snap and it took a lot longer to recover and by the time I recovered I was already off the track and could not get back on track."

Team principal Steve Nielsen added: "A small mistake, which on other tracks would have been fine, but on this track you get punished for it in certain places."

Antonelli, meanwhile, started the weekend as if he was determined to turn around the decline in his fortunes in which team-mate George Russell has cut his championship lead from 68 points to 25 over the last three races.

The 19-year-old Italian was 0.190 seconds quicker than McLaren's Lando Norris in second place - and a massive 1.285secs quicker than Russell.

"Rears [tyres] felt too cold, sliding a lot," Russell said over the team radio during the session. "But not 1.2 seconds cold."

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Antonelli, who was only sixth fastest and Russell eighth in the first session, said: "Was a massive turnaround with the car, because P1 we struggled a lot.

"It was a good change but of course a lot of work to do because Red Bull is quick, McLaren was up there. Long run felt very strong as well."

Mercedes trackside engineering director Andrew Shovlin added: "It was a messy first session where we didn't have the car in the right place. We thought there'd be more grip than there was, but the drivers were a lot happier with the car in the afternoon.

"Not a great lap for George but it was only one lap. If that doesn't go well you look like you're off the pace.

"He felt he didn't have the tyres ready for the start of the lap. A few corners were it looks like he might have underestimated the grip level."

Antonelli was also in impressive form on the few long-run laps completed in the session, emerging 0.3secs quicker than Norris on average and 0.4secs clear of Russell.

Norris said: "P1 not great. P2 a little bit happier, I am still not very happy with the car, it is still very difficult to drive but we seemed a bit closer, but we are always pretty close on Friday in practice, I think we just show more pace than our competitors. We shouldn't expect anything differently from normal."

The world champion confirmed he, like all the drivers, was suffering for the energy-hungry nature of the circuit. This is leading the cars to run out of electrical energy on the straights, meaning the engines go into recovery mode and the cars lose speed long before the end of the straights, a phenomenon known in F1 as "clipping".

"There is just lack of deployment everywhere," Norris said. "Every single straight. The worst one is through Blanchimont. We go from almost 320km/h to almost 270km/h because we just have no battery left. Every single straight we're clipping."

Max Verstappen's Red Bull, third fastest on the single-lap qualifying simulation runs, was matched with Antonelli on his long run, when equalised for traffic and length.

Verstappen, who topped the opening session, said: "It has been all right for me, didn't have big problems, the car has been in quite a good window. You see the real gap but it is nothing shocking, it is expected.

"It is just a bit of a tough track with the energy management, seems like we're a bit slow on the straight compared to some of our competitors, but balance-wise it was OK."

Hamilton was 0.747secs off the pace as Ferrari struggled with the age-old Spa compromise of working out the right downforce level to ensure competitive straight-line speed, while having enough downforce for speed in the corners of the middle of the lap.

"Spa is still amazing to drive," said the 41-year-old. "Through corners is great, it's just on the straights the engine dies. I don't know what they're going to do to fix that in the future - the engine should just keep pulling.