Lewis Hamilton says extensive floor damage to his Mercedes Formula 1 car on the opening lap of the Mexican Grand Prix cost him several tenths per lap.
Hamilton suffered a broken floor in a chaotic first lap as the right side of his car was struck by Max Verstappen's left rear wheel as they battled for position through Turn 1.
Hamilton could not see the damage when driving, but he did feel a big difference in the car's handling.
As can be seen in the above photograph, the damage is to the vertical slots alongside the edge of the floor, along with the diagonal ones.
These let the airflow moving over the top of the floor spill outwards to build a seal to the floor, stopping any dirty air from leaking in and disrupting diffuser performance.
The damage means one half of the diffuser would have been working harder than the other, and the aero balance would have shifted towards one side of the car.
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- From no hope to victory
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- Mercedes' tyre gamble
- Battling a damaged floor
Hamilton said that he had to adapt his car's settings to try to overcome the handling imbalance.
"I didn't actually know how much was missing or what was damaged, but the balance was quite a lot different," he said.
"The rear end was quite weak, so I was particularly sliding around a lot in the high-speed [sections], so I had to change my settings quite a lot and had to drive it a little bit differently because I couldn't attack the same way on the entry of corners because the rear stability wasn't the same.
"I'll probably find out later on just how much we were losing, but I would imagine a good couple of tenths probably, just from rear floor damage.
"It's quite a sensitive area around where the tyres is."
The scale of damage to Hamilton's floor in Mexico is larger than in Australia where a missing element of the floor cost him performance as team-mate Valtteri Bottas won.