Valentino Rossi's time at Ducati may have been his least successful in grand prix racing, but the Italian admits it will be 'very emotional' when he walks out of the team garage for the final time on Sunday evening.

Rossi is heading back to Yamaha after failing to win a race at Ducati, and will make his M1 return during testing at Valencia on Tuesday and Wednesday.

"Yes, it will be the last race with Ducati, and for sure we're arriving at the end of this story between us, that unfortunately never gave good performance, or the level we expected," said the seven time MotoGP champion, who has taken just three podiums from his 34 starts on the Desmosedici.

"It will be difficult on Sunday because after you work for a long part of the year with the people, and you then have to stop and change teams. It will be very emotional. Even if the result was not fantastic, we had a good time together outside of the track, and we tried the maximum."

Rossi starts the final round sixth in the championship, eight points behind Gresini Honda's Alvaro Bautista and sixth ahead of Tech 3 Yamaha's Cal Crutchlow.

"We will stay concentrated, stay focussed and last year here was not too bad in practice but then we had the crash in the first corner of the race. We also have to wait and see for the weather and understand the new surface."

But Rossi is already eagerly awaiting the post-race test, which will mark his first Yamaha laps since 2010, as he re-joins the factory with which he won four of his premier-class titles.

"It will be very, very interesting on Tuesday especially for me to try to understand which level I can achieve with the M1 and what feeling after two difficult seasons," Rossi declared.

"I can't wait for the test. But first we have to stay concentrated and try to get the maximum points on Sunday for the battle for fifth place."

33-year-old Rossi will ride alongside former team-mate and newly crowned double world champion Jorge Lorenzo for the next two seasons at Yamaha.