Lewis Hamilton believes Ferrari is “nearly a second quicker” than Mercedes on the straights alone going off Friday’s times during practice for Formula 1’s Belgian Grand Prix.

Hamilton was almost a second adrift of FP2 pacesetter Charles Leclerc as Ferrari ended up dominating Friday’s practice sessions in Belgium, while the Briton also encountered problems that limited his running in the morning.

Speaking about his disjointed day, Hamilton said: “It was not a great start for us in FP1, we had a problem with the throttle and I basically lost power, so I was idling just with the RPM to try and get back.

“Then I managed to fix it a little bit with a couple of switch changes, and got it back and went back out and had another problem, so it was a little bit of a mess.

“Then I got some laps towards the end, but it wasn’t spectacular. Then we made some changes to the setup, it was quite far off into FP2, and it was feeling a lot better, but still have work to do.

“I don’t know about the gaps, obviously the Ferraris are quite quick, they’re like nearly a second quicker than us just in a straight line down to Turn 5,” he added.

“That’s quite impressive, but we’ll just keep chipping away at it. We’re clearly up in the mix, which is a good thing.

“I think the Ferrari particularly in the first sector, it’s quite a big chunk. I assumed we gained some of it back in the middle, and the last one I think is quite close between us.”

Hamilton, who reckons Mercedes’ new engine upgrade is worth less than half a tenth of a second in lap time performance, admitted the gap to Leclerc “sounds terrible”.

“All that time is on the straights generally. There’s not a lot we can do to generally catch that up,” he explained.

“They’ve always been quick all year long on the straights, so I kind of had a feeling this weekend would work really well for them.

“We just kind of have to somehow apply the pressure another way, if we don’t have it on pure pace. I think the long run was very strong. I’m about to find out now, but I was told Vettel’s times.

“He was in the high-50s I think, 51, mid-51s, and I was in the low-to-mid 50s on the long runs. So it will be interesting to know what fuel and tyre life that we had. That will be interesting to see. If we’re quick in the race, that could be good.”

Teammate Valtteri Bottas, who outpaced Hamilton by less than a tenth in FP2, said Ferrari was “killing” Mercedes on the straights.

“We always knew coming here Ferrari will be strong, also Red Bull, but Ferrari has been really strong today and really killing us on the straight lines,” he added.

“That’s how it goes. For sure we’re trying to find every bit of performance we can for tomorrow.

“We need to make big steps if we want to battle with them. At least from practice one and practice two, we made some decent gains and got a bit closer, but still we’ll see.”