Red Bull owner Dietrich Mateschitz believes that Sebastian Vettel has improved over the winter and is now "stronger than ever".

13156 - Vettel 'is stronger than ever'

Having dominated the 2011 season to claim back-to-back world championships, Vettel is favourite to add to his tally in 2012. While Red Bull has had the quickest car over the past three seasons, a change to the technical regulations could bring the field closer together but Mateschitz said that as long as the RB8 is competitive then Vettel will deliver.

"Sebastian has got better and is stronger than ever," Mateschitz told La Gazzetta dello Sport. "He has trained over the winter break like he never did before now and he certainly won't disappoint. What he needs for the third title is a competitive car and we will be able to evaluate in the first tests in Jerez (in February) where the team is heading."

Mateschitz also backed Mark Webber to be closer to Vettel this season having only won one race in 2011.

"Mark is one of the best. His age is relative and he's one of the physically best prepared drivers...with a new number one mechanic at his side he will certainly not make life easy for Sebastian."