hmmm. It's really damn hard to break the front sprocket compared to the rear. Maybe they misquoted him? The pic is definitely of the rear, but if the front sprocket failed I'm sure the chain could have broke the rear sprocket like that (you can see all the scratch marks on the rear sprocket from the chain rubbing the side of it).^^^ hmmmm pulled the 'front sprocket' quote from the MotoGP interview with Edwards??? So maybe the front did that to the rear???
http://www.motogp.com/en/news/2013/Edwards+and+Corti+both+hit+trouble+in+Qatar
-Jamie M.