Jenson Button thinks McLaren are "clutching at straws" after he and team-mate Sergio Perez failed to score points in the Canadian Grand Prix.
It brought an end to McLaren's run of 64 consecutive points finishes as Perez finished 11th and Button 12th.
"We were worse here than we have been all year compared to the frontrunners," said Button. "We've got work to do.
"I'm looking forward to the next race at Silverstone, it can't be as bad as here. We're clutching at straws."
McLaren are suffering one of the worst starts to a season in their history currently lie sixth in the constructors' championship, 164 behind leaders Red Bull.
In the drivers' standings, Button trails leader Sebastian Vettel by 107 points, while Sergio Perez is a further 13 adrift.
In Canada, McLaren were always on the back-foot after a poor qualifying saw the team send Button out too late to complete a late flying lap in the second session and he ended up 14th, two places behind Perez.
McLaren team principal Martin Whitmarsh admitted that the team then made a series of strategic errors during the race.
"It was a tough afternoon," he said. "We got it wrong. With Button, we should have started on the 'prime' [medium] tyre. We really stayed out on the 'option' [super-soft] too long, stayed in traffic and lost a lot of time.
"In the case of Jenson, we set him lap time targets which were too slow - and he could have gone much faster. He could have pushed into the points.
"It was one weekend where we didn't get it right. We were not quick enough to be at the front but we should have been able to get in the points."
Button added: "The team gave me a lap time, but it wasn't quick enough. We got the calculations wrong. Once I started pushing, the pace was quite a bit better."
I've never been so pleased to get out of a car. It was quite painful out there. We got lapped, easily lapped. It was like we were in a different category."
McLaren traditionally perform well at Circuit Gilles Villeneuve and have won the race five times in the last seven races, but they failed to reproduce that form this year.
"At least we get the information from here to understand why we don't work around a circuit where we used to be so strong," said Button. "That should help us with development for this year and also the future."
Despite the disappointing result, the 2009 world champion remained positive ahead of his home race - the British Grand Prix - which takes place in three weeks.
"I'm still looking forward to my home grand prix," he said. "Are we going to be quicker there? Yes.
"We're not going to be on the podium I don't think, but getting into high points has got to be our aim."