▁, ▁M oto GP ▁had ▁changed ▁its ▁rules ▁to ▁allow ▁four - stroke ▁ 9 9 0   cc ▁engines ▁to ▁race . ▁At ▁the ▁time ▁Duc ati ▁was ▁the ▁fast est ▁bi ke . ▁In ▁, ▁M oto GP ▁reduced ▁the ▁engine ▁size ▁to ▁, ▁and ▁Duc ati ▁continued ▁to ▁be ▁the ▁fast est ▁with ▁a ▁bi ke ▁that ▁was ▁marked ly ▁quick er ▁than ▁its ▁riv als ▁as ▁was ▁displayed ▁by ▁Case y ▁St on er ▁on ▁tracks ▁with ▁long ▁stra ights . ▁ ▁For ▁, ▁Duc ati ▁Mar l bor o ▁Team ▁campaign ed ▁their ▁Des m osed ici ▁GP 9 ▁with ▁former ▁World ▁Champions ▁Case y ▁St on er ▁and ▁Nick y ▁Hay den . ▁Duc ati ▁also ▁supplied ▁customer ▁b ikes ▁to ▁Pr am ac ▁Racing , ▁with ▁M ika ▁Kal lio ▁and ▁Nic col ò ▁Can ep a ▁r iding ▁for ▁the ▁team ▁in ▁ 2 0 0 9 . ▁ ▁N ine - time ▁world ▁champion ▁Valent ino ▁Ros si ▁rode ▁for ▁Duc ati ▁Cor se ▁for ▁the ▁ ▁and ▁ ▁seasons . ▁Ros si ▁returned ▁to ▁the ▁Yam aha ▁team ▁for ▁the ▁ 2 0 1 3 ▁season . ▁ ▁For ▁, ▁Duc ati ▁Team ▁rac ed ▁with ▁Nick y ▁Hay den ▁and ▁the ▁Italian ▁r ider ▁Andrea ▁D ov iz ioso . ▁In ▁ 2 0 1 4 ▁Cal ▁Cr utch low ▁te amed ▁up ▁with ▁D ov iz ioso ▁for ▁the ▁season , ▁and ▁he ▁left ▁at ▁the ▁end ▁of ▁the ▁year .