Sebastian Vettel labeled his second practice session on Friday as "horrible" and caused in part by overly aggressive set-up changes to his Ferrari SF1000.
Vettel concluded his day way down the order in P16 after suffering two spins and running a run on Pirelli's soft compound.
"We’ve had a mixed day, the first session was okay, the second session was horrible," said the German.
"We tried something with the car and I think it was very aggressive and probably not what we needed.
"We were happy and we thought it would work but I don’t think it did, so we will see for tomorrow."
Despite his set-up troubles, Vettel was nevertheless confident of having a shot at Q3 in qualifying.
"I think Q1 should be fine to make it through to Q2, and then I think Q3 could be possible – maybe it’s a little bit better than last week – but I reckon it will be very tight," he reckoned.
"It’s a short lap, the gaps between the cars are nothing. The midfield has always been tight this year so it will be even tighter."
Vettel's poor FP2 session at least wasn't hindered by any mechanical issues, which was a luxury that his teammate Charles Leclerc did not enjoy after a driveshaft failure sidelined the Monegasque early on.
But Leclerc was also hopeful of an improvement of the Scuderia's fortunes on Saturday.
"We were actually better than expected I have to say, and FP2 was also good until the failure on my side," said Leclerc. "So hopefully it will be a good day tomorrow."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
