The Ferrari team suspects it will struggle to reach Q3 in Singapore after a low-key performance in Friday practice.
Kimi Raikkonen and Giancarlo Fisichella ended up only 14th and 16th in the second session, and team manager Chris Dyer does not think that bodes well for qualifying.
"Today's performance was definitely nothing to get excited about," he said. "The interruption to the session complicated the running of our planned programme, but overall we have gathered sufficient data to be as well prepared as possible for qualifying and the race.
"Tomorrow, our aim is to get both cars through to Q3. It won't be easy, but we will do our best."
Fisichella was similarly pessimistic about Ferrari's chances.
"It was a rather difficult day," he said. "The car is very nervous and I have yet to find the ideal set-up. Now, I must sit down with the team to try and prepare as well as possible for qualifying and the race. My aim is to improve on my result from Monza, but I know that won't be easy.
"The track was very slippery and sometimes I had a bit of graining on the tyres. Unfortunately, I never managed to do a long run with the soft tyres, because of the red flags following [Mark] Webber's accident. This compound is definitely quicker by three to four tenths, but there is a question mark over the consistency of its performance."
Team boss Stefano Domenicali pointed out that a slump was always inevitable as Ferrari was now focused on its 2010 car, but hoped that a good result could still be salvaged.
"Clearly, when evaluating today's free practice times, one has to consider the various unknown factors, but it is equally clear that our situation looks pretty difficult," he said.
"Besides, if so many other teams continue to bring significant technical updates to the track, while for the past two months we have frozen the development of the F60, then we can expect to find ourselves in this situation.
"All the same, we must now concentrate on ourselves and try and make the most of the package we have, as indeed we have done in the past few races. If we do a good job, we have seen that the results can follow."