Formula One championship leader Sebastian Vettel was the fastest on the final day of a special in-season testing session with new tires.
The three-time defending series champion completed 78 laps in his Red Bull at Silverstone on Friday during the tire test sanctioned by the sport's rulers to quash the threat of a revolt by teams.
Vettel topped the timesheets with a lap at 1 minute, 32. 894 seconds. Adrian Sutil set the pace in the morning, but ended up second-fastest, around three-tenths of a second slower than Vettel.
In-season testing was banned in 2009 over cost concerns, but these unprecedented sessions were allowed to allay safety fears after concerns about tire blowouts on the same circuit at the British Grand Prix earlier this month.
Mercedes was banned from the sessions after holding unsanctioned testing in May.
The new compound of tire tested at Silverstone will be used from the Hungarian Grand Prix next weekend and for the rest of the season.
''We had three days of ...