Vettel could only qualify fourth, behind both Mercedes and teammate Kimi Raikkonen, in Baku on Saturday.

"The result is OK, but we're not entirely happy obviously," said Vettel. "This morning didn't help [when he lost FP3 running time with a hydraulic problem], but that's not an excuse. We are doing enough laps.

"In the end I was alone and had no tow in the last sector, but I'm not a big fan of excuses. I could have done a bit better, but probably P3 was the maximum.

"I think everybody was surprised by how much Mercedes improved [in qualifying]. However, we must be careful not to read too much into it. If you're totally comfortable with your car on a circuit like this one you can easily gain quite an amount of time."

Buoyant over race pace

Vettel believes that the raw pace advantage of the Mercedes will be less apparent in the race on Sunday.

"We're a little more confident that we've found a bit more in the car, so I wouldn't worry too much," he added. "Obviously it's not ideal where we qualified, tomorrow is a long race and the pace should be good."

When quizzed by NBC Sports over Ferrari's one-second pace deficit to Mercedes today, Vettel fired back: "Today they did, I don't think they have [it] tomorrow.

"We start P4, if I improve by one position that's a podium, and we see. I think Mercedes will also be quick tomorrow, but I have no doubts that we can be a match.

"On Friday, our long-runs were very good. But this doesn't help much when you start a bit further back."

Additional reporting by Stefan Ehlen