Sebastian Vettel accepts that Ferrari is not as close to Mercedes as it has been in recent races, after Nico Rosberg and Lewis Hamilton locked out the front row of the grid in Spain.
Vettel beat Mercedes to victory in Malaysia while Kimi Raikkonen split Hamilton and Rosberg at the most recent round in Bahrain.
However, during qualifying at the Circuit de Barcelona-Catalunya, Vettel was eight-tenths down on Rosberg and will start the race from third position.
"Realistically they are quick, we are not on pole or second so they showed every single session this weekend [that] they are very competitive with either tyre, so I expect them [to be] strong tomorrow," he said.
"Hopefully we will be closer as we’ve been better in race pace but I think it will be difficult.
"I think we expected them to be very strong here because of winter testing and I’m sure they have improved. But conditions are completely difficult, it’s true that the gap is there and probably bigger than the last few races.
"I don’t think it’s one thing only, lots of things you throw in the bag, maybe we are struggling a bit more this weekend but I’ll look forward to where we are tomorrow."