In 2015, when Stoner was still contracted with HRC as a very part-time test rider, Dani Pedrosa was injured and Stoner offered to fill in for him for two of the MotoGP races, the Argentina and Austin MotoGP races. Stoner hadn't raced at these tracks in his racing career , so was keen to participate in both these races. HRC shied away and instead chose their reserve rider (Hiroshi Aoyama?) to ride Pedrosa's bike in these races. It went downhill from there between Stoner and HRC. Stoner also felt under-utilised as a test rider at HRC and felt that Honda didn't really listen to his inputs on bike development. Ducati seized on this situation and offered Stoner a more involved role in developing the Desmosedici MotoGP bike and Stoner was game for it. The earlier crash on the Honda at Suzuka (due to a stuck throttle) where he broke some bones did not help the relationship either. This is the background to Stoner's signing up with Ducati where he'd already won a championship (in 2007?).