Alonso confident of matching Red Bull

Alonso's best lap was more than one second slower than pace-setter Sebastian Vettel, but the final times disguised the Ferrari drivers' full potential - with the Spaniard on Vettel's pace in the first two sectors on a quick lap before getting it wrong and running off track.

That lap has left Alonso quite confident about his team's potential for the Singapore weekend - as he eyes adding more valuable points to his tally to close the gap on championship leader Mark Webber.

When asked by AUTOSPORT where he felt Ferrari's potential was compared to Red Bull Racing, Alonso said: "I think we are close to them. We were more or less close with the hard tyre and then I didn't complete the lap with the soft tyre, so I guess they are in front.

"They are still a little bit in front of us, a couple of tenths, but hopefully we can fight with them and are close enough tomorrow."

Alonso said his error late in second practice was simply the result of driver error.

"I braked late for Turn 18," he said. "Then I put reverse to get back on the track and, when I put first gear to rejoin the circuit, the engine stopped. So I finished the session there.

"Unfortunately we lost the last 20 minutes when we were ready to try something else - but no big problem."

Alonso experimented both with and without the F-duct during Friday's free practice session, and he said he expected the team to decide to stick with the blown wing from Saturday.

"We were trying some different parts of the car in the first session," he said. "But we were concentrating on the F-duct, trying to see what the best solution is.

"At the moment there isn't a clear picture. We need to analyse more data but I think first plan a) is to use it. It was okay, it was working fine, so normally we should use it tomorrow definitely."