Jenson Button has admitted to being at a loss when it comes to understanding McLaren's sudden loss of form which saw it scrapping over the minor places in its home grand prix at the weekend.

Although the Woking team has slowly dropped away from the race-winning performance it displayed at the start of the season, Silverstone was something of a nadir for 2012 with both Button and team-mate Lewis Hamilton relegated to bit parts while Red Bull and Ferrari - both of which struggled with their cars at the start of the year - stole the limelight and the top four places.

With the unpredictability of the season also throwing the likes of Lotus and Mercedes into the mix as regular podium threats, McLaren's demise is costing its valuable championship points but, while Button's title challenge was already in freefall after adding just five points from six races to victory in Australia and second in China, Hamilton was also badly hampered by the lack of potential in front of his home crowd on Sunday.

Button's challenge was blunted on Saturday when, after featuring in the top two in the morning's dry free practice session, he was undone by the lottery of wet qualifying and tumbled out at the first hurdle. Although he would eventually start 16th, the 2009 world champion faced a tough task in his quest to bolster his championship tally, and lucked into a single point when Nico Hulkenberg ran wide while battling Bruno Senna on the final lap.

Hamilton, meanwhile, also qualified lower than he would have wanted, in eighth, and, despite appearing to make early progress, found himself back in his original position when the chequered flag fell. To make matters worse, the championship's top two drivers, Fernando Alonso and Mark Webber finished in reverse order at the front of the field to extend their advantage over the chasing pack, which was headed by Red Bull's Sebastian Vettel and Ferrari's rejuvenated Felipe Massa.

"We don't have the pace of the top three teams," Button admitted to Reuters, "At the moment, we are racing the Williams, the Sauber and the Force India. I won't take anything away from the guys driving the Williams and the Saubers, but we have a lot of experience in this sport and we feel we are getting the best out of this car now. That's where we are at the moment and, personally, I don't feel they had the best weekend - if the Williams and Sauber had had a good day, they would have beaten us, so we've got a lot of work to do.

The Briton also conceded that the finger of blame for McLaren's disappointing weekend pointed directly at the car, as the team got its strategy and pit-stop procedures right in a race made tricky by the first prolonged dry running of the three days.

"We just didn't have the pace," he confirmed, "The balance doesn't feel too bad - on high speed corners, the car is reasonable, on low speed it's not fantastic but not bad- so, when you see a car come past you like you're just stood still, it's a surprise. I don't know where we are missing out, I don't know how so many teams can be getting it right and we can't. It is amazing to think what the rest of the guys are driving around in. They must be on rails. I wonder what would happen if you put another driver in this car - I bet they would get a real shock. ...

"We thought we had it right. We had such a great start to the year. It was what everyone said we had to do, we did that - and then it has dropped off. I don't think the top teams have any tricks. We are still struggling with tyre temperatures - I put on hard tyres at the end and was going well but, when I got behind other cars, suddenly my tyre temperature had gone. [The car] didn't grip the circuit - you turn in and it shudders across the circuit."

With McLaren dropping out of the top three positions in the teams' championship, there is a lot of head-scratching to be done ahead of the back-to-back races in Germany and Hungary that take F1 into its mid-season break, but Button is confident that the team can bounce back.

"We've got to improve," he said, "We've got a technical meeting on Tuesday, which is going to be quite a sombre meeting, but [everyone in the meeting is] going to be quite aggressive about trying to improve this car."