(CNN)For Formula One fanatics it was a thrilling  spectacle  -- the sport's top two drivers going head-to-head for the drivers' championship title. That Nico Rosberg and Lewis Hamilton were teammates, from the Mercedes stable, made it all the more enthralling. Not only did they go corner-to-corner on the circuit, they also traded verbal volleys away from the pit lane. For Rosberg, who was ultimately beaten to the world title by the Briton and had to deal with plenty of criticism along the way, it wasn't the first time he'd felt like an outsider. As testing for the 2015 season continues, he says last term provided some trying moments but he insists he can't think of a better teammate than Hamilton.
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Mercedes' Nico Rosberg admits to dark times during the 2014 F1 season
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But the German says he overcame disappointment of finishing second immediately
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Rosberg and F1 champion Lewis Hamilton had fractious relationship last season
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The 29-year-old says their partnership will continue to be an intense one
Prior to last season's runner-up berth, @placeholder's best finish in an F1 season was sixth back in 2013.