The German lost one of his four allocated power units at Monza when a leak was found on his upgraded engine ahead of qualifying. Since then, Rosberg has had to run his current unit more conservatively than Hamilton, which could leave the championship runner-up at a disadvantage on Sunday.
“It’s going to be difficult because I have an extremely old engine, having lost my fourth engine, so I have a lot of miles on it and that’s costing me straight-line speed,” Rosberg said.
“It’s going to be a difficult weekend as a result, but I’ll just have to be quicker in the corners!
“I’m always slow on the straights all weekend because it’s very, very high mileage because it’s a very old engine.
“This track is an engine track, and it was already difficult in Brazil and the race before that, but now on the straights this is an engine track and it will cost me in lap time.
“It is what it is and I just have to make the most of it.”
Rosberg’s power deficit did not prevent him from setting the pace during Friday free practice, where he also looked more comfortable than Hamilton in terms of tyre management over long runs.
While naturally pleased to kick off the F1 season finale on a high, the German, who is seeking a sixth consecutive pole position and third win on the trot at Yas Marina Circuit, warns against reading too much into the lap times.
“I’m feeling good, it’s a good start to the weekend, even though Lewis has been showing his pace on one lap and in general.”
“It’s clear that he still has some reserve for sure. Today is not the real picture.”
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