Valtteri Bottas described Mercedes’ W09 as "difficult to drive" during practice for Formula 1’s Hungarian Grand Prix.
Mercedes was off the pace through Friday’s sessions, with Lewis Hamilton fifth and Bottas sixth, the latter finishing a second adrift of leader Sebastian Vettel in second practice.
Both drivers set their best times on the Soft tyres after making mistakes on their respective Ultrasoft efforts.
Hungarian Grand Prix: FP1 results | FP2 results | Photo Gallery
“Today was not an easy day; the car was difficult to drive and I struggled to get laps together, especially in FP1,” said Bottas.
“We managed to improve the set-up for FP2, but there’s still more work to do.
“This is a difficult circuit, you need to have a well-balanced car in order to get all the corners right and we need to get the car more stable.
“We struggled to get the Ultrasoft compound tyres working consistently and had some issues with overheating.
“It is difficult to overtake here, so track position is very important and the less stops you can do is always going to be better.
“Red Bull and Ferrari are as quick as we expected; I think it’s going to be very close.”
Hamilton added that preserving the rear tyres is the main issue facing Mercedes.
“As we expected, the Ferraris and the Red Bulls were quite quick and had a little bit more pace than us, so we’ve got some work to do tonight,” he said.
“This is a tricky circuit and the tyres are overheating; looking after the rear tyres is the biggest issue.
“The temperatures today and the layout of the track – corner after corner after corner – made it really tricky for the tyres as there’s no time for them to cool down.”
