American Ben Spies will replace Ducati-bound Valentino Rossi at Yamaha next season, the MotoGP team said in a statement Friday. The 26-year-old, who won the World Superbike Championship with Yamaha in 2009 and is seventh in the current MotoGP standings, makes the step up to the factory team from Yamaha Tech 3. “Ben has shown great promise in his first 10 MotoGP races,” said Lin Jarvis, managing director of Yamaha Motor Racing. “He has learnt rapidly and recorded strong results. We believe that Ben will be a future title contender.” World champion Rossi is leaving for Ducati after becoming frustrated with Yamaha also boasting championship leader Jorge Lorenzo of Spain. The increasing superiority of MotoGP over the Superbikes championship was also displayed Friday when Ducati announced it would not run a team in Superbikes from next year.