ROME, Italy - Seven-times World champion Valentino Rossi denied newspaper reports claiming he is about to retire from Moto GP.He has had a miserable time since leaving Yamaha to join Ducati, finishing seventh in 2011 and managing only one podium finish. Three races into the 2012 season and already he is down to ninth place.ONGOING STRUGGLEDespite a report in Britain's Daily Telegraph, Rossi insists he is not calling it quits and said on his Twitter page: "Ciao guys, the rumours about my retirement at the end of the year are not true! See you in Le Mans."I have no intention of retiring at the end of the season, it's just a made-up story. Often things are written in newspapers not because they are true but because they sell copies."Rossi has been critical of his Ducati since the first race this season, leading to rumours that he is not happy with the team.YEAR WITHOUT WINSThe Telegraph, citing an unnamed source close to the popular Italian, claimed on its website that Rossi would retire at season's end, when his contract comes to an end. Similar stories are circulating about Casey Stoner.Rossi is one of the most successful riders of all time in his sport with seven championship wins between 2001 and 2009 and two others in the lower classes.However, the 2011 season was the first in which he didn't win a race.