Fernando Alonso said he wasn't concerned by the pace of his rivals after practice for the Korean Grand Prix, with the Spaniard insisting that Ferrari was only focusing on itself during the two Friday sessions.

Alonso was fourth quickest over the course of the two sessions, with his best lap being three-tenths of a second slower than title rival Sebastian Vettel.

The current points leader admitted that it was difficult to compare his performance with his rival given the programme Ferrari was running.

"It's hard to say where we are compared to the others, because today, we focused mainly on ourselves, working this morning on a comparison of various ideas relating to car configuration and, in the afternoon on the tyres," he said. "We must wait till tomorrow to have a more precise picture of the situation.

"The track improved a great deal from one session to the next: it's a phenomenon that's particularly accentuated here, because there's hardly any racing on this track and this morning, it was particularly dirty. Let's hope the situation improves for tomorrow because it's always more fun driving when the track offers at least some grip."

Team-mate Felipe Massa enjoyed a solid start to the weekend with the seventh quickest time and the Brazilian said he was now eager to maintain his performance into the remainder of the weekend.

"I'd say this weekend has got off on the right foot, but the important thing is to continue down this path tomorrow on Sunday, when it really counts," he said. "Our car seems pretty good on this track, which is cause to be hopeful, even if we will only discover the truth tomorrow in qualifying.

"From what we could see this afternoon, in the second session, the difference between the Soft and the Supersoft is definitely a big one: we seemed comfortable on the two of them, on both low and high fuel loads. Now we are trying to prepare as well as possible for qualifying, which looks like being very closely contested: there is some very strong opposition and we will have to do everything perfectly if want to be able to match them."