Formula One legend Michael Schumacher has expressed his 'shock' at Sebastian Vettel' domination over his team-mate in his unstoppable march to a fourth title.
Vettel ended the 2013 season 198 points ahead of Mark Webber with 13 victories to Webber's nil, clinching the drivers championship with three races to spare.
Speaking in a season review for his former team, Mercedes, Schumacher said Vettel did a "great job".
"Look at his team-mate, that's the reference point you've got to take.
"He won all those races.. Mark Webber won none. That's pretty shocking, I'm glad I'm not his team-mate."
See more in the video above.