Singapore GP: Ferrari yet to decide on new rear wing after Friday practice

The new wing features larger flaps and new endplates, and was seen as a key development as Fernando Alonso attempts to hold on to his world championship lead.

But after initial tests on Friday in Singapore, the team reverted to the original wing design.

Ferrari's race operations manager Diego Ioverno said the team was still analysing what to do for the rest of the event.

"It was taken off in the afternoon, after we had done the tests," he told reporters in the Singapore paddock.

"We wanted to do a comparison with the other wing, the one that we could call the baseline.

"The numbers are still under investigation. At the moment I cannot say if we are going to use it or not.

"We finished the session with the other wing, so it may happen that we stay with the baseline one."

Asked if he was worried that this meant another Ferrari development had proved ineffective on track, Ioverno replied: "I think it is quite a common aspect for all the teams.

"We have no possibility to track-test the stuff, we rely on the windtunnel numbers and for everyone when you bring something on the track it might not be working as expected, so obviously it is not a pleasure if it happens.

"It is a bit of a concern also for the future, but it is something that we have to face as everyone has to face because we have this limitation on testing.

"I cannot say that we are happy for sure, but we are not desperate."

Ioverno was still cautiously optimistic about Ferrari's Singapore form, with Alonso third-fastest in practice two using the old wing.

"I think on Friday it is normally very difficult to understand what is going on, because of fuel load and track conditions," Ioverno said.

"I think that we have to understand what everyone has to understand, which is the real life of the tyres. How the drivers look after the tyre?

"We are still analysing the data, but it seems with one of the two compounds we are not in bad shape, but I think the major factor will be how long the tyres will last and we will learn it only on Sunday, I guess."