Lewis Hamilton has warned Mercedes will have a "very, very close" fight with Ferrari at the British GP after Sebastian Vettel led Friday practice.

Ferrari landed the first blow in their battle with Mercedes for supremacy at Silverstone after car updates to the SF71-H delivered an immediate on-track improvement.

"We try to kill their magic," said Sebastian Vettel after setting the fastest time of Practice Two in a Ferrari car fitted with a new floor.

"Everything we put on the car seemed to work," added Vettel.

"It's a small step in the right direction. What's more important is the balance was there from the beginning of the day and I felt quite happy with the car. I had a good rhythm straight away so, for a change, we had a good Friday."

Sunday's British GP underway at 2.10pm, Sky F1 coverage from 12.30pm

Qualifying at 2pm on Saturday

P2: Vettel ahead of Hamilton

Vettel's 0.187 seconds advantage over Hamilton, with Valtteri Bottas another two tenths behind, was the first time in 2018 when a Ferrari car had finished Friday in front.

But Hamilton said he was relishing the challenge from Ferrari - and the evolving Silverstone circuit.

"The track is the fastest it has ever been," said Hamilton. "We're flat out through Copse and Turn 1 and through Turn 2 with the DRS - it's insane how fast it is. The faster this track gets, the better it gets. It has to be the best track in the world, it feels like driving a fighter jet around the track.

"With the speeds we're going now and the G-forces we're pulling, I think it's going to be the most physical race of the year."

On the battle with Ferrari, Hamilton admitted: "It's going to be very, very close this weekend, the Ferraris are really fast. We're in for a serious fight which is great for the fans and I hope that we can pull through."

Round one to upgraded Ferrari but Red Bull struggle

Mercedes have won at Silverstone for the last five years in a row, making Ferrari's unexpected surge all the more potentially significant.

"We try to kill their magic, that's what we've tried in the last years," said Vettel. "Here and there we've succeeded quite well. It's true that they are very, very strong around here and you'd expect them to be very strong tomorrow. But I hope we can be there, it's going to be close. That would be very good news."

A week on from their Austrian GP victory, Red Bull had a poor day - lacking speed, reliability and track time.

After a gearbox glitch in first practice, Verstappen crashed out on cold tyres at the start of Practice Two and admitted afterwards: "We're definitely not fighting for pole."

2:14 Watch Red Bull's Max Verstappen as he spins off in Practice Two at the British GP. Watch Red Bull's Max Verstappen as he spins off in Practice Two at the British GP.

Team-mate Daniel Ricciardo, who was fifth quickest, added: "We weren't fast. There are a few things we can improve with the balance but it's quite a big gap to Ferrari and Mercedes. We will try a few things but we'll also have a think about how to be the car which makes its tyres last on Sunday."

With Silverstone basking in unusually hot weather, Ricciardo continued: "Managing the temperatures will be key to having a better race car. For qualifying, we will try to do what we can but Ferrari and Mercedes are too fast over one lap. But for the race we will try to find a few little secrets."

Mercedes v Ferrari: Recent British GP history Mercedes have won the last five British GPs dating back to 2013

Lewis Hamilton has won the last four in succession and five overall

Ferrari last won at Silverstone in 2011 and started on pole in 2012

Sebastian Vettel's only British GP win came in 2009 for Red Bull

Are Ferrari ahead in Mercedes territory?

Commentary from the Sky F1 team:

"I just have the feeling that this is a hugely significant session" - David Croft.

"This is a Mercedes circuit, it has been for a long time, and Ferrari have come here and topped them. It might not be a race victory for Mercedes - I think that Ferrari update is working pretty well round here" - Anthony Davidson.

"I think it's highly encouraging for Ferrari that they're in amongst the Mercedes" - Martin Brundle.

4:55 Sky F1's Anthony Davidson is at the Skypad to analyse all the incidents in Friday Practice ahead of the British GP. Sky F1's Anthony Davidson is at the Skypad to analyse all the incidents in Friday Practice ahead of the British GP.

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