NICO Rosberg completed a practice double on Friday after he topped the timesheets in both sessions for the British Grand Prix.
Rosberg, who overcame a hydraulics failure in the morning to pip team-mate Lewis Hamilton, posted a fastest lap of one minute 34.155 seconds to lead the way at Silverstone.
Hamilton was only fourth, half-a-second down on Rosberg, with Ferrari's Kimi Raikkonen in second and his team-mate Sebastian Vettel, on his 28th birthday, in third.
Towards the end of the session, Hamilton reported over the team radio that his car was "all over the place", and he "couldn't make it go any faster."
The Briton heads into his home grand prix leading Rosberg by 10 points in the championship, although the German has won three of the last four races.
While it was business as usual for Rosberg at the front, the same could also be said for Jenson Button towards the back of the pack.
The 2009 world champion, who could be making his final Silverstone appearance, arrived at his home race in the midst of his worst-ever start to a Formula One campaign.
And his fortunes failed to improve on Friday as he completed just 16 laps in the second session - the fewest of any other driver.
At one point, the Englishman, who spent the majority of the opening session kicking his heels in the McLaren garage, was asked if he wanted another lap. He sternly replied: "No. Something is wrong with the car," before returning to the pits. He ended the day a lowly 17th, three seconds slower than pacesetter Rosberg.
The afternoon session was red-flagged on two occasions. Firstly, when Romain Grosjean beached his Lotus in the gravel at Luffield, and then for a brief spell in the latter stages after Roberto Merhi, in his Manor, spun.
Grosjean, who did not take part in any running this morning after Briton Jolyon Palmer once again occupied his seat, was later pictured helping his mechanics with the clean-up operation on his Lotus in a desperate bid to get some laps under his belt.
With 20 minutes left he emerged on track and ended the session 14th, completing 21 laps.
It was not long after the session restarted that Fernando Alonso also ended up in the gravel at the same corner as Grosjean - but where the Lotus driver had faltered, double world champion Alonso managed to keep his McLaren running.
As with his McLaren team-mate however, the Spaniard, who has retired from the last four races, was seen wrestling with his car throughout the session. He finished 15th, 2.5sec slower than Rosberg.
Mercedes meanwhile, were handed a reprimand from the stewards for covering Rosberg's car as it was returned to the paddock in the opening practice session after he stopped on track.
