McLaren boss Martin Whitmarsh has admitted to failing Jenson Button during the Canadian Grand Prix.
Button endured a torrid time in Montreal, as an oil leak resulted in the 32-year-old sitting out much of Friday's practice session before he ran out of new sets of tyres during qualifying.
"Jenson is a great racing driver, but we served him badly over the weekend," said Whitmarsh.
"His rear tyres were completely shot because we didn't long-run with his suspension set-up on Friday.
"That was our fault. We didn't give him a car he could perform in."
Button finished 16th and is now 43 points adrift of teammate Lewis Hamilton.