World champion Casey Stoner told long-time rival Valentino Rossi to mount a serious challenge to his crown after a lacklustre season left the Italian without a race win for the first time in his 15-year career.

Australian rider Stoner, the 2007 and 2011 champion, wants to see a healthy challenge launched by Rossi’s Ducati team, but doubts their potential to eclipse his Honda outfit.

“They are saying that they completely revamped 90 per cent of the bike, but they did that in the middle of last year.

“They changed the bike back to front and top to bottom and nothing much changed,” said Stoner.

“I’m hoping, for Ducati’s sake, that they can put together a competitive bike this year because the championship needs it.

“Regardless of what the riders want, everyone needs as many manufacturers at the front as possible.

“Yamaha and Honda want competition; unfortunately Kawasaki and Suzuki are gone from the championship, so we need all bikes at the front.”