(CNN) -- Red Bull are threatening to scupper Jenson Button's hopes of a seventh win from eight Formula One races this season, after trouncing their rivals in Friday's practice sessions for Sunday's British Grand Prix at Silverstone.
The Red Bull of Sebastien Vettel looks the car to beat ahead of Sunday's British Grand Prix at Silverstone.
Sebastien Vettel and Mark Webber were head and shoulders above the rest of the field in both the morning and afternoon sessions, with Vettel on top on each occasion, narrowly edging out his Australian team-mate.
The young German's fastest lap of the day came in the dying embers of first practice, knocking Webber off top spot with a time of one minute 19.400 seconds, with the 21-year-old only 0.056 seconds slower in the second session.
Webber, who finished 0.282 seconds adrift in the morning, managed to halve that deficit later on, but the rest were left floundering.
The first period saw world championship leader Button -- bidding to continue his dominance this season in front of his home supporters -- third-fastest in his Brawn GP, 0.827 seconds down on Vettel.
Then, in the second period, it was the remarkable sight of Force India's Adrian Sutil riding high in third position, albeit 0.685 seconds behind.
Williams' Kazuki Nakajima was fourth, followed by Fernando Alonso in his Renault and Button's team-mate Rubens Barrichello.
World champion Lewis Hamilton, who won the last year's race by a remarkable margin of 68 seconds in the wet, was a respectable seventh in his McLaren, just under a second down.
The top 10 was completed by Toyota's Jarno Trulli, Nico Rosberg in his Williams and the Renault of Nelson Piquet.
Robert Kubica, bottom of the standings in the morning, managed to climb to a more respectable 11th in the afternoon for BMW Sauber, with McLaren's Heikki Kovalainen 12th.
Towards the bottom, in 17th and 18th, were the Ferraris of Felipe Massa and Kimi Raikkonen, with Toro Rosso's Sebastien Buemi at the rear and languishing by 2.212 seconds.