Christian Horner: New rules have given Adrian Newey his mojo back

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Red Bull boss Christian Horner says F1's new regulations have given designer Adrian Newey "his mojo back", though he still believes Mercedes are the "clear, clear favourites" for 2017.

Despite the rules shake-up placing a greater focus on aerodynamics, a long-time strength of the Milton Keynes outfit and its legendary technical chief, Red Bull had a low-key pre-season with the RB13. Instead it was Ferrari who stole the headlines in Barcelona, posting the quickest time of the winter despite clearly sandbagging its true performance.

Horner still thinks Mercedes, who have won the last three drivers' and constructors' championships, will be the team to beat this season, which commences on March 26 in Australia.

"Mercedes is the clear, clear favourite," Horner told the official F1 website. "They have won 50 races in the last three years, we've won five and Ferrari three. Do I have to say more?

"Mercedes are total favourites. Yes, we've made a good car -- a good basis of a car that we will hopefully be able to develop effectively through the year. Renault has had a busy winter as well and hopefully the TAG Heuer-branded engine in our car will perform well this season. How well -- and what the others will find -- is pure speculation."

With many predicting a relentless development "arms race" through 2017, especially among the top teams, Horner also used the interview to give Red Bull's rivals a warning about a revitalised Newey.

"Adrian definitely has his mojo back again. Right now he is juggling two projects -- the Aston Martin car and the RB13 -- but he's got a great team and together they are doing a super job. Adrian is contributing effectively into that. It's great to see him enthused again about Formula One."