Rubens Barrichello has suggested that Ross Brawn should have 'fought' to retain the drivers who helped to lead the ex-Honda F1 operation to double world championship glory in 2009 - as mystery continues to surround the identity of Nico Rosberg's team-mate at Brackley in 2010.

Between them, Barrichello and team-mate Jenson Button triumphed eight times over the course of the campaign - and on only six occasions did neither of them make the podium. However, Button has elected to jump ship to join compatriot and title-winning predecessor Lewis Hamilton at McLaren-Mercedes next year, and Barrichello will extend his own record-breaking F1 career into an incredible 18th consecutive season at Williams, meaning Brawn GP - now re-baptised Mercedes Grand Prix, following the Stuttgart manufacturer's takeover - will begin 2010 with all-change on the driver front.

Triple world champion Niki Lauda has already opined that Brawn could come to regret letting Button slip through his fingers over a failure to reach agreement on financial terms [see separate story - click here] - and whilst expressing his 'surprise' at the Briton's departure, Barrichello agreed that had the driver/team principal roles been reversed, he would have done more to keep the pair on-board.

"Honestly, if I were the owner of the Brawn team, I would have fought for the retention of the two drivers for the work that was done during the season," the 37-year-old Brazilian told Spanish newspaper Diario AS. "Button's decision took me by surprise; I never imagined that he too would leave."

Despite many musing that the seeds of his own parting had already been sown as early as his post-German Grand Prix outburst at the N?rburgring in July - in which he emotionally and publicly accused the team of 'making me lose the race' - the Paulista insisted that his Williams switch was motivated by a desire he had held since his youngest days, when the Grove-based concern was regularly at the sharp end of the field. Barrichello's hero and countryman Ayrton Senna competed for Williams in 1994, the year in which he was tragically killed at Imola.

"My decision was taken early," explained the eleven-time grand prix-winner. "It was a childhood dream to drive a Williams, so I signed the contract very rapidly."