LONDON, England - Valentino Rossi's legacy as MotoGP's greatest rider is in danger of being further eroded by another lacklustre season with Ducati and the Italian is under no illusions about how difficult this year could be.The season will open at the Losail track in Qatar on Sunday and Rossi, 33 and a nine-times World champion across the classes, will have to work hard throughout the year if he is to improve on 2011's championship seventh place on the uncompetitive Italian bike.'THINGS TO FIX'"We worked hard over the winter and although we went the wrong direction at one point," he admitted, "we once again managed to find the good feeling with the GP12 that we'd had in the first test."I'm a realist and I know well that our times are still a long way off and that there are still some things to fix. We won't be able to address some of them right away but it's also true that both we at the track and the guys back home now have direction - we must try to do as well as we can."2011 World champion Casey Stoner, who used to ride for Ducati, is favourite to retain the title for Honda.RETIREMENT DENIEDRossi, who last won the championship in 2009, moved to Ducati from Honda in 2011 but the dream union of Italy's most famous rider and most famous motor-cycle manufacturer did not work out as planned. Ferrari's similar woes in F1 have led pundits to wonder whether Rossi made an error in not switching to four wheels when he had the chance with the Italians in 2006 and again in 2009.The death of friend and compatriot Marco Simoncelli in the Malaysia MotoGP last October hit him hard but rumours of retirement were soon denied.Their current plight after poor testing times means small milestones are all Rossi has left to cling to."We won't completely redo the bike during the season, but we'll try to progress little by little," he said.