Mercedes boss Toto Wolff has said he was surprised by Ferrari's pace in China and they have given the Silver Arrows "something to think about".
Mercedes found themselves half a second down on the two Ferrari cars as the battle for pole was exclusively between Sebastian Vettel and Kimi Raikkonen.
Valtteri Bottas could find no improvement on his final Q3 run, while Lewis Hamilton aborted his last lap and was forced to settle for a second-row start behind his team-mate.
Ferrari have now locked-out the front row for a second consecutive race and Wolff admitted that Mercedes are on the back foot.
"No [we didn't expect Ferrari to be so strong]," Wolff told Sky Sports.
They've been really strong all day. Their qualifying performance they put one on top and we really have something to think about.
"It's tricky. We are lacking grip. You can fall out of the window by the tyres getting too hot or being too cold. It's two extremes like we had in Bahrain. I think it's a tyre issue.
"Tomorrow it's expected to be a lot warmer so I hope we have done the right thing set-up-wise and we have better pace in the race than Ferrari.
"There is not a lot of strategic plays either. If we have pace then we can undercut or overcut."