Valtteri Bottas says he knows where he went wrong with the setup on his Mercedes Formula 1 car for second practice on Friday in Mexico after dropping from first to sixth on the timesheets, with the Finn taking confidence from his early pace.

Bottas finished four-tenths of a second clear of the pack in FP1, heading up a Mercedes one-two, but dropped back to sixth in second practice as Red Bull and Ferrari both turned up the wick.

Despite appearing to struggle for pace, Bottas admitted after the session he had taken a wrong turn with his setup, giving him confidence in how to turn the situation around.

"First practice was good, I really enjoyed it. It is such a fun circuit to drive because it has quite a low grip, so it is definitely challenging," Bottas said.

"We made some set-up changes for FP2 which went in the wrong direction. So in the end of the session we went back to the original setup.

"For some reason I also struggled to get the tyres to work in the second session. That's why it didn't look as good as the first one.

"But I think it was a positive day overall, I'm looking forward to qualifying."