By ESPNSTAR.com staff
The Red Bull driver has already racked up 25 grand prix victories in his career and is the favourite to win the drivers' championship this season. He trails Stewart by just two races and is well-placed to become the sixth-most successful driver of all time with only Fernando Alonso, Michael Schumacher, Nigel Mansell, Ayrton Senna and Alain Prost ahead of him on the list.
In fact, even Mercedes' Schumacher, widely considered by many as the best driver of all-time, only had one world championship and 10 race wins to his name at the age of 25
But Stewart, who is the only Briton triple world champion, does not rate Vettel as highly as the statistics seem to suggest. He feels that the Red Bull mechanics are the true stars of the show and the reason why Vettel has been so successful over the past three seasons.
"If you've got a superior car, it's relatively easy to win the championship," Stewart told BBC Sport
"To really show you're one of the greatest, you have to deliver when you haven't got the best machinery."
"I have the highest respect for Sebastian, but he could not have achieved what he has without the [Red Bull design chief] Adrian Newey factor.
"I'm a big Sebastian Vettel fan. He completely dominated the Korean Grand Prix and drove in such a mature fashion for a 25-year-old. It was more than impressive.
"Vettel has established himself as the favourite and Alonso is now on the back foot.
"Led by Adrian Newey, Red Bull have bounced back from a slow start to the season and have now come up with superior equipment."
The 73-year-old has also heard of the recent rumours linking Vettel with a switch to Italian marquee Ferrari but he feels that the young German should not let monetary concerns dictate his career and stick with the Milton Keynes team.
"I think that's premature. He would be mad to leave Red Bull at the present time.
"I know there would be a difference in their basic salary, but he's in a position where he's winning grands prix.
"He's won 25 races and is going to knock me off my perch before the end of the season - but he's only 25 and still has time to move."
Vettel currently leads the championship with 215 points with Ferrari's Alonso six points behind with four races remaining in the season.