Vettel explains where Ferrari 'struggling' in Sochi

Sebastian Vettel concedes that Ferrari have "catching up to do" after trailing Mercedes by more than half a second in practice for the Russian Grand Prix. Lewis Hamilton went quickest to lay a marker down to his title rival in FP2, but Vettel could not match him.

Hamilton went quickest of all on Friday, clocking one minute 33.385 seconds, having previously kept within three tenths of Vettel in FP1, despite running with slower tyres.

Come FP2, where teams simulate qualifying and long-runs, Vettel was 0.543 seconds down on Hamilton's time on matching rubber, with the Red Bulls sat between the Silver Arrows and Ferraris.

Vettel has said he must win all six of the remaining six races of the year if he is to beat Hamilton to the title, but that appears unlikely at this stage.

Summing up his session, Vettel said: "Tricky. Obviously we looked quite far away from the rest of the field, so not ideal.

"I think we're struggling a bit for one lap but also in the long run. We went through our tyres a bit harder and quicker than the rest, so we need to have a look.

"But I think also, just looking at ourselves, it wasn't a good day in terms of feel for the car. I think there's more that we need to get to."

Having expressed frustration with Ferrari's strategy in Singapore last time out, the German was again tetchy over the radio after his long-run sims came in heavy traffic, but he was not too concerned.

"That's Friday for you," he said. "Sometimes you have better Fridays, sometimes not.

"For us it wasn't a particularly clean run in the end, but good enough.

"As I said, we struggled with the tyres with and without traffic. Certainly [running] in traffic doesn't help, but I think we have some catching up to do."

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