Mercedes Grand Prix finally confirmed one of the worst-kept secrets in the F1 paddock earlier this week by officially unveiling Nico Rosberg as one of its two drivers for the 2010 campaign.

However who will occupy the second seat remains a mystery. A number of men have been touted as possibilities including record-breaking F1 legend Michael Schumacher, out-of-work BMW-Sauber refugee Nick Heidfeld and Ferrari's displaced 2007 world champion Kimi Raikkonen.

Also thought to be in the frame is former Canadian Grand Prix winner Robert Kubica - who already has a contract with Renault, but could yet be on the look-out for a drive should the French manufacturer opt to pull the plug on its F1 operation, as well as the likes of ex-McLaren-Mercedes driver, Heikki Kovalainen and Adrian Sutil.

So who do you think the former Brawn GP team should opt for?

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