Red Bull dominated the final practice session at sunny Silverstone, but fastest man Sebastian Vettel had a scary moment on Saturday morning.
The entire nose section of the German’s RB6 came loose, which if a chassis problem could prove a major obstacle for the team ahead of qualifying in 90 minutes.
It was a scary moment for the 23-year-old and 2009 British grand prix winner, as he ran wide at the ultra-fast new Abbey corner.
But mechanics fitted a new nose in the garage and appeared satisfied that the problem is solved.
McLaren, having experimentally run a blown exhaust on Friday, still did not look quick after reverting to the Valencia spec, despite sending test driver Gary Paffett back to Woking by helicopter to trial solutions in the simulator.
"We will persist with it," Paffett told the BBC, "and hopefully we’ll test it out see where it went wrong and have it improved by the time we get to Hockenheim."
Red Bull’s Mark Webber, just three hundredths behind his teammate on Saturday morning, said: "McLaren are a class operation and will be back."
Just a tenth off the pace was Ferrari’s Fernando Alonso, and he was merely a tenth quicker than Nico Rosberg in the Mercedes.