Red Bull team boss Horner says Webber's efforts over off-season helped earn him contract extension

Webber has bounced back from a tough 2011 campaign alongside a dominant Sebastian Vettel to fight for the championship again this year. And Horner believes that the Australian had to work hard over the winter to return to form.

"Mark has come back with renewed energy and enthusiasm for Formula 1 this year," said Horner at Hockenheim on Thursday. "The win [in Brazil] at the end of last year did him a world of good and he wintered well.

"He has been very competitive and he is second in the world championship. He is one of only two drivers to have won two grands prix so he's back at the top of his game.

"It was evident to us that he came back after the winter with a refreshed approach and it was obvious that he put a lot of thought and hard work into his winter programme and came back with a renewed enthusiasm."

Horner added that it made sense to finalise the contract extension earlier than the team had initially planned to given Webber's current form.

"We had an agreement in principle so we had the opportunity to talk," he said. "But in the aftermath of Silverstone it was very easy to conclude rather than wait, and to get on with it rather than have the distraction of speculation.

"Mark's confidence is high. Being the team-mate of a guy who is the youngest ever double world champion would be tough for any driver. Sebastian is the benchmark but Mark has the strength of character to deal with that.

"Mark has made it very clear that he wants to compete and win championships and he obviously felt that his best chance to achieve that was to remain with Red Bull."