Red Bull’s Max Verstappen was fastest in second practice at the Belgian Grand Prix, with Daniel Ricciardo’s Renault also ahead of the Mercedes.
Lewis Hamilton was third fastest as the top three were separated by only 0.096 seconds.
Mercedes’ Valtteri Bottas was down in sixth, behind Red Bull’s Alexander Albon and Racing Point’s Sergio Perez.
The times are unlikely to be representative of real performance.
Ferrari, in particular, were out of position, with Charles Leclerc 15th and Sebastian Vettel 17th.
The Italian team were always expected to be off the pace around the high-speed Spa-Francorchamps circuit, given their straight-line speed deficit this season, but it is unlikely they will be that slow come qualifying on Saturday.
Even the Alfa Romeos, which have been significantly slower than Ferrari so far this season, were ahead of them in this session, and there is no obvious reason why the form of the two teams, who use the same engines, would have switched so dramatically.
The same is likely to be the case for Mercedes, who have dominated qualifying so far this season and would not be expected to be in third and sixth places.
But Hamilton said he believed the field had closed up on Mercedes.
“It has been a good day,” Hamilton said. “I love driving around this track, it’s incredible. Got plenty of running in.
“It is very close out there. I think the Red Bulls are just a little bit quicker at the moment but even the Racing Point is right with us and Daniel Ricciardo in the Renault was very close. That makes it exciting. We have some work to do to try to dial in the car a bit more.
“We are only in the seventh race. The field is going to get closer and closer and it is already showing that. We seem to be so close with everyone and we have to understand why, whether they have taken a step or we have taken a step back or downforce levels, who knows? But I am excited for an interesting race.”
Verstappen said: “I think they are still struggling a bit with the balance. I expect them to be stronger tomorrow. You can see in the long runs they are very competitive, I am not expecting to fight for pole position but if we can be a bit closer that would be good.”
The fragmented nature of the race-simulation runs made it even harder to divine a clear picture of relative pace.
Hamilton, who leads the championship by 37 points after six races, did only one lap on soft tyres on his race-simulation run before a virtual safety car caused by Ricciardo’s Renault stopping out on track with a loss of hydraulic pressure.
That one lap by the Mercedes was almost identical to the first time set by Verstappen on his race-simulation run.
After that, Hamilton switched to the hard tyre, but managed only one lap on that before the session was stopped because of debris on track from a sponsorship hoarding.
It restarted but only in time for a final seven minutes of running.
Behind Bottas, McLaren’s Lando Norris was seventh fastest, ahead of Renault’s Esteban Ocon, McLaren’s Carlos Sainz and Alpha Tauri’s Pierre Gasly.
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