Lewis Hamilton has admitted that McLaren cannot match the pace of Red Bull at Interlagos this weekend if the weather remains dry.
The McLaren driver was third and fourth fastest in Friday's two practice sessions, but more than half a second adrift of pacesetter Sebastian Vettel in each. Hamilton is happy with the setup of his car but believes he will need rain – which is forecast for Saturday – to challenge for a place on the front row.
"I'm getting everything I can out of the car out there," he said. "I could have a tenth here or there, but when they have a big gap those guys can relax a little bit more. My car felt good, just a little low on downforce. Unfortunately our limit at moment is still a good half second off the pace of Red Bull.
"The Red Bulls and Ferraris seem generally quicker, so they must have more downforce than us, but if it's wet it makes it more of a lottery and makes it a bit easier for us. My car is much better than last year's in the wet, so I should fight through to Q3 and for pole.
"In terms of pure pace in the dry, we can't compete with the Red Bulls. But rain, reliability, engines... these things are going to play a major part in the next two races, and I hope that it's an advantage for us."
Jenson Button reported struggling with a lack of grip throughout practice today, but was happier with his car during higher-fuel runs.
"I had a lack of rear grip and also lack of front grip," said Button. "I was playing around with balance a lot, trying to work with the car. The high speed is now working well, the low I'm still struggling a little bit with the front end.
"This afternoon I ran on lower and higher fuel, and higher was definitely better for me. I was just struggling for balance, low speed corners are tough, there's no grip. But the high-fuel run was much better."