HOLDING BACK? Mercedes' Nico Rosberg may have dominated the practice sessions but he believes Lewis Hamilton (above) isn't showing his true pace.Image: AFP / Philippe Lopez
Abu Dhabi - Nico Rosberg believes an old "high mileage" engine in his Mercedes may hinder him in his hopes of reeling off a third straight victory ahead of team mate and newly-crowned triple world champion Lewis Hamilton in Sunday's Abu Dhabi Grand Prix.
The 30-year-old German topped the times in Friday's second free practice session run through twilight after a hot day at the Yas Marina circuit, leaving Hamilton one-tenth of a second in arrears at the final race of the season.
'Plenty in reserve'
But Rosberg said that he was not confident in his car and did not believe Hamilton, who topped the times in the opening session, had shown his true speed.
"I would say it has been a good start to the weekend, for me," said Rosberg.
"But I say that even though I know Lewis did not show his true pace on one lap and, it is clear, that he still has plenty in reserve.
"So, today is not the real picture. In general, it is going to be difficult for me because I have an extremely old engine.
"I lost my fourth engine of the year and the one I have has a lot of miles on it - and that is costing me straight-line speed.
"So, it is going to be a difficult weekend. I just have to go quick in the corners."
6th pole possible?
Rosberg, who is seeking his sixth straight pole and hoping to complete a hat-trick of successive wins, clocked a best lap in one minute and 41.983 seconds ahead of Hamilton who recorded 1min42.121.
Sergio Perez was third for Force India, four-tenths adrift.
Rosberg added: "I am just always slower on the straights the whole weekend as I have very, very high mileage...
"And it is very old, the engine - and this track is an engine track. In Brazil, it was difficult and the race before, but here is the ultimate engine track so it costs more lap-time, but it is what it is."
Daniel Ricciardo was fourth for Red Bull, who earlier confirmed they have agreed a deal for an unnamed engine for next season, ahead of four-time champion Sebastian Vettel of Ferrari and Daniil Kvyat in the second Red Bull.
Kimi Raikkonen was seventh in the second Ferrari ahead of Nico Hulkenberg in the second Force India and, surprisingly, two-time champion Fernando Alonso in his McLaren Honda.
Pastor Maldonado was 10th for Lotus, whose participation in the event was only confirmed after F1 commercial ringmaster Bernie Ecclestone paid their expenses.
The struggling Lotus team are expected to be taken over by Renault for next season, but Renault have yet to make any definitive statement on their plans for next year.
Earlier in the day, Hamilton had topped the opening free practice session and given an on-track answer to his critics after negative comments were made about his lifestyle.