When Michael Schumacher walked away from Formula 1 in 2006 after seven world titles, he looked content with a career in which he’d re-written the record books. But it became clear in 2009 that he was hungry for more.

Twice a champion with Benetton and five times with Ferrari, Schumacher redefined the way drivers did business. Ruthlessly focused and efficient, Schumacher was loathed as much as he was loved.

Schumacher’s ruthlessness is best shown by his post-retirement return to Mercedes, the manufacturer which first helped him into the limelight in sportscars way back in 1990. There were jeers, rather than cheers, from the passionate Italian tifosi, who felt betrayed after lauding him at Ferrari, but Schumacher’s decision to return to Formula 1 ultimately proved not to be his canniest move.

The German struggled to get back up to speed after a couple of seasons away leading to constant speculation around a second retirement. He ended the season ninth in the points, his lowest score since his debut season back in 1991.

Now beginning the third season of his comeback, Schumacher will need to do much better in 2012 for any rumours of another retirement to go away.