PARIS, France - Valentino Rossi, reduced to playing the role of MotoGP's sleeping giant during his disastrous spell with Ducati, is eager to emerge out of his enforced slumber in 2013 now that he has returned "home" to Yamaha.Rossi, who had a paltry three podium places to show for his ill-fated two seasons with Ducati, will again be teamed with Jorge Lorenzo in what promises to be a fascinating, though probably sparky, 2013 partnership.CLOSED ON HIGH NOTEWhile the effervescent Italian, who won four of his seven MotoGP titles with Yamaha, now finds himself in the unusual position of having something to prove, Lorenzo approaches 2013 as a double World champion. The likeable Spaniard prevailed in his gripping season-long tussle with Dani Pedrosa, claiming the title in the penultimate race in Australia when his Honda rival crashed.Despite missing out on the crown, Pedrosa closed his own campaign on a high note with victory in the season's finale in Valencia with Lorenzo crashing this time - in spectacular fashion.Pedrosa's 45th win of his career pushed him up to 332 points, 18 shy of Lorenzo. Third in Valencia was outgoing champion Casey Stoner in his last race before retirement. The Australian's Honda team marked the occasion by hanging a sign over the track wall on which was written "Going fishing".Stoner, highly critical of Rossi's move back to Yamaha, dismounted from his bike and declared: "It's fantastic to end (my career) this way, a big thanks to everyone, to my supporters all these years, there are a lot worse ways to go out."'NEEDED TO BE STRONG'Lorenzo, for his part, claimed his title achievement had left him liberated. "It's been a big emotion because 2012 has been tougher than my first World title (2010) because I knew my competitors were stronger and more constant and I knew I had to be more constant than them."When I first came into MotoGP I needed to learn from my mistakes, know my limits and try not to go over those limits so for this reason I am very proud of my evolution."I feel emotional for the toughness and the hard competition. I needed to be strong and really focused. For this reason I now feel liberated of the weight off my shoulders."It's probably just as well Stoner will not be around in 2013, given the way he castigated Rossi's dismal time at Ducati, accusing the Italian of "jumping ship". As for Rossi, the move should inject fresh life into his faltering fortunes."It's a return for me and the feeling was like having never been away," he said.'AT A CERTAIN AGE'Reflecting on his ill-fated spell with Ducati, Rossi told BBC Sport: "It was a dream, it was a great and important bet to try to win for Ducati, but unfortunately we have no way. Two very difficult seasons. We tried lots of things but were never able to fix the problems. We had some good races and a few good results but not what everyone expected."We lost the bet."Of his prospects for 2013, the 33-year-old added: "I'm at a certain age and I don't know how many years I will continue in MotoGP so I have to race with the best bike I can. Fortunately I've won more or less everything so I need to enjoy it to have the right motivation. I need to arrive at the circuit every weekend with a chance to fight for victory. It will be difficult but that is why I changed teams."If Rossi can re-ignite his old sparkle Lorenzo & Co are in for a dogged battle in 2013.