Ferrari shows the pace at Monaco GP as Mercedes struggles

But as time ebbed on, Button eased himself up the order, and finished a respectable 1.5 sec slower than Hamilton's best effort and less than two tenths of a second adrift of Stoffel Vandoorne in the sister McLaren. Vettel initially went fastest on his first lap on the ultra-softs, before making a 0.039s improvement on his second attempt.

His time was over a full second faster than the closest Mercedes of Lewis Hamilton in eighth, while Valtteri Bottas could only manage 10th.

The Mercedes driver has matched already the late Brazilian's three championships and sailed past his 41 career wins and on Saturday, at the Monaco Grand Prix, he can equal Senna's 65 pole positions.

"We had zero degradation, more or less", Pirelli's F1 boss Mario Isola said. "I can't explain it because I don't understand it".

"We didn't have the greatest day", said Hamilton.

"Practice one was actually really good and we were quickest, but then in second practice we just struggled to extract the grip from the tyres and we were sliding around a lot".

"I'm not sure why the tyres weren't working, but the difference between the two sessions was night and day, black and white". "We are lacking data so it's about sticking our heads together, staying calm and trying to work as well as possible on Saturday morning".

Hamilton, with only one Monaco pole to his credit so far, played down talk of such an experience even if he loved racing around the circuit.

Cape Town - Red Bull team principal Christian Horner believes Ferrari set the standard for the Monaco Grand Prix this weekend. Mercedes title rival Lewis Hamilton had been fastest before lunch. "We did some changes and it always got better".

The Mercedes driver is now six points behind the Ferrari driver and a win at Monaco will take him to the top of the leader board. "I've never seen so much passion in the years I've been with this team".

It was the first time Button has driven a 2017 spec vehicle and he admitted the new machines will take some getting used to.

Button finished the day a respectable 12th, four hundredths of a second slower than Stoffel Vandoorne in the sister vehicle.

The 18-year-old Canadian lost the rear of his Williams on the exit of Massenet before thudding into the wall and rolling to a stop at the bottom of Casino Square.

In a surprisingly orderly session, nobody damaged their cars over the hugely unpopular kerb on the exit to the Swimming Pool, and only Romain Grosjean went off properly after locking his Haas' brakes at Ste Devote, before spin-turning back into business. Jolyon Palmer also had an interrupted session, his Renault crawling to a halt with a power unit failure.

  • Joanne Flowers