Having helped Sebastian Vettel reach the very top in Formula 1, Red Bull advisor Helmut Marko admits he is "upset" by the errors he has made this season.

The German has been culpable on several occasions this season, most notably causing collisions in France, Italy and Japan as well as his infamous crash at Hockenheim.

Lewis Hamilton has taken advantage to put himself on the brink of a fifth world title, something Marko didn't expect earlier in the year.

“I considered Vettel to be the favourite for the title, but he made a lot of mistakes which upsets me,” he was quoted by PlanetF1.

Also Read:

• Vettel accepts Hamilton & Mercedes had it "too easy" in recent races
• Hamilton calls on the media to show "respect" to Vettel after criticism

The Austrian doesn't think the 31-year-old's situation has been helped, however, by how Ferrari has conducted themselves.

“When you see that Mercedes now rely on Hamilton, then why not swap around Kimi and Sebastian, as could have been done in Austria?" he queried.

“Or why in qualifying did they not put Kimi on the track before Vettel, as could have been done in Monza?

“Now, Vettel no longer has the right to make mistakes. But even if he doesn’t make any, it will be hard for him to win the title.”