Shanghai: Former world champions Jenson Button and Michael Schumacher both saw their Chinese Grand Prix victory hopes ruined by pit-lane errors, but refused to blame their teams for wrecking their chances.
First to go, about a quarter of the way through the action in Shanghai, was the Mercedes of Schumacher, who had started on the front row of the grid with team-mate Nico Rosberg, the eventual race winner.
As Schumacher made off to exit the pit after a tyre change, a Mercedes mechanic could be seen frantically waving his arms in a vain bid to stop him.
But the 43-year-old was gone, only to slow up and stop shortly afterwards as he was forced to meekly bow out, his chance of a first race win since coming out of retirement over.
Minutes later Mercedes confirmed on Twitter: "Michael's right front wheel was not fitted properly at the stop leading to his retirement."
Looking disappointed, though not angry, Schumacher said: "The front wheel got loose. We need to check why and exactly what happened.
"I feel a bit sad for one of our boys, but I will hug him later on and calm him down."
Mercedes were later fined 5,000 euros for an unsafe release.
Button survived his pit-lane problem, but saw his chance of snatching victory go and had to settle for second in his McLaren.
"I stopped on the markers and had a problem on the rear," the Briton revealed.
"I got stuck for maybe 10 seconds," he added, allowing Rosberg to streak into a clear lead that he never looked likely to surrender.
"The first two (stops) were very good. These things happen."