Mercedes boss Toto Wolff is expecting a dog fight with Red Bull at the Bahrain Grand Prix, the opening race of Formula One’s 2021 season.

Red Bull appears to be the car to beat at this stage of the season, a reversal of the last seven years of unmatched Mercedes dominance. Max Verstappen topped both of Friday’s practice sessions.

Reigning world champion Lewis Hamilton and Valtteri Bottas both said the Mercedes had improved since testing at the same venue two weeks ago, but Wolff is sure Red Bull still leads the way.

“The night has fallen and the conditions haven’t come towards us. It’s a real dog fight” Wolff told Sky Sports after the second session.

“When you overlay the fastest laps and even the long runs, it’s just so very close that every kilogram in fuel load can have a very big swing so we don’t really know.

“We are definitely closer here than we were in testing but I wouldn’t know where to position us versus Red Bull.”

Despite seeing an improvement, Bottas still had complaints about the car at the end of the second practice session. A broadcast radio message revealed the Finn had found the car “undriveable” in the closing stages.

“The last long run we did was pretty inconsistent,” Bottas said. “I couldn’t really put any laps together as the car was, as I said, undrivable at times. A bit puzzled but it’s Friday and that’s why we practice.”

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