Helmut Marko says Red Bull are "not working in the right direction" after a difficult Friday in wet-dry conditions at the British Grand Prix.
Max Verstappen was the highest placed Red Bull during Friday practice at Silverstone, but the Dutchman was able only to place fourth fastest.
Verstappen was only moderately satisfied with his day but team advisor Marko was unable to take many positives from the opening day of the weekend.
"We haven't got the set-up right yet, we're not getting the right balance in the car," the Austrian is quoted as saying by MotorsportMagazin.
"We are suffering from both oversteer and understeer and can't find grip in the slow corners. We are not working in the right direction yet."
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Red Bull drivers complained of strange noises
During the second hour, both Red Bull drivers complained of strange noises emitting from their cars.
"It came from the bodywork, something made contact somewhere," Marko explained.
He declined to confirm or deny that the problem was related to the newly installed bodywork at the rear of the car, but also made clear he was not too concerned.
He said: "It's nothing serious."
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