Red Bull team principal Christian Horner believes that a difficult 2014 has made Sebastian Vettel a better driver.

The four-time world champion endured a barren season, while teammate Daniel Ricciardo took three race wins and finished ahead of the German in the drivers' standings.

However, Horner is adamant that the trials and tribulations over the past 12 months will do Vettel good in years to come.

"I think it was a very difficult year for him - a character building year, in many respects," Horner told Autosport. "He's had a lot of bad luck and things didn't go his way more often than not.

"On top of that, he was not happy in the car with the regulation changes from 2013 into 2014. He's a tremendously talented guy and I think it's the first time he's had a team-mate who has challenged him as well.

"It's been a difficult year, but not once has he let his chin drop or kicked the team. I think ultimately he'll take away a lot of valuable lessons from this year."

Vettel replaced Fernando Alonso at Ferrari after signing a three-year contract with the Scuderia.