Valentino Rossi has made his first public comments since last Friday's announcement that he will quit Ducati and return to Yamaha for the 2013 MotoGP season.

The seven time MotoGP champion, who has taken just two podiums since joining Ducati for the start of 2011, posted the following (translated) comments on his official Twitter page (@ValeYellow46):

"It was a great shame not to be able to be competitive on the Ducati. It would have been a great satisfaction for me and for all the guys who worked with me and fun for all our tifosi. I'm sorry.

"Anyway there are still 8 GPs until the end and we will keep trying our best to do some nice races. Ciao all from Indy. #valeducati"

Rossi will ride alongside former team-mate Jorge Lorenzo at Yamaha for the next two years. His Ducati replacement is yet to be announced.

Round eleven of the 2012 MotoGP championship takes place at Indianapolis this weekend. In the official Ducati Team preview Rossi, presently eighth in the standings, commented:

“This break served as an opportunity to make important decisions for the future, but now I want to return to thinking about the races because we want to improve and during the weekend it's important to focus completely on what we have to do on the track.

“Indianapolis isn't one of my favourite circuits, although I do have a win there. It's a particular track because it's one of those that goes in the opposite direction, so the lines are a bit strange in many of the corners. It's a tricky track, but we'll try to do our best and have fun.”

Ducati team manager Vittoriano Guareschi may not have liked Rossi's decision, but he at least believes it will allow the team to 'concentrate'.

“The past month has been very intense for everyone, but now things are clearer,” he said. “We can therefore concentrate on our work on the track as we continue to improve our bike so that Vale and Nicky can finish the season on an upward trend.”

Rossi won from pole at Indianapolis in 2008, with Yamaha. The Doctor finished tenth last season.

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