Max Verstappen said his Red Bull "was not really nice to drive" during Friday's two practice sessions ahead of the Chinese Grand Prix as he was forced to conserve tyre life on the softer compounds, rather than focus on outright performance.
Verstappen was third-fastest behind Sebastian Vettel and Valtteri Bottas at the end of the day, and would have been closer than two tenths of a second to the Finn were it not for a poor exit out of the final corner on his quickest lap.
Although Friday running suggested that Red Bull are back in the mix with Ferrari and Mercedes after being decidedly third best in Bahrain, Verstappen wasn't wholly satisfied with his day's work.
"The tyres are pretty weak, they degrade quite a lot the softer compounds," Verstappen told Sky Sports. "So it's not really nice to drive. You're really just managing tyres."
Verstappen confirmed that Red Bull's off-colour Bahrain outing was down to a set-up error, but is confident it has been fixed in Shanghai.
"Of course it's always a question mark," he said. "But I think we were all quite confident that if we could solve that it would look already a lot better and I think that showed today, it's not too bad."
Team-mate Pierre Gasly was 10th, almost a second off Verstappen's top time as the Frenchman's adaptation to life at Red Bull continues.