Rossi rode the Ducati Desmosedici for the first time this afternoon at Valencia. Image: MCN.

Nine-time world champion Valentino Rossi has made his official debut aboard the Ducati Marlboro Team machine that he’ll contest the 2011 MotoGP World Championship aboard.

The 31-year-old Italian has completed his first laps aboard the Desmosedici after rain delayed the morning sessions at the official post-season test at Valencia in Spain on Tuesday.

Rossi debuted on an all-carbon Ducati with minimal design on the bike, however he was sporting a trick set of Dainese leathers designed custom for the test.

The test will see Rossi test both the big-bang version of the GP10 that was used this season, as well as a screamer version to put through its paces.

Rossi was the third rider on track this morning, with Ducati test rider Franco Battaini the first before Loris Capirossi completed a number of sighting laps.

The test gave the opportunity for photographers to get world first images of Rossi on the Ducati.

Also set to circulate this afternoon at Valencia is Casey Stoner aboard a Repsol Honda without sponsor logos, which is largely attired in Australian colours and features a large kangaroo on the side.

Ben Spies will also make his official debut as a Yamaha factory rider in place of Rossi.

Other riders to debut on new rides include Pramac teammates Loris Capirossi and Randy de Puniet, Moto2 World Champion Toni Elias at LCR Honda, Hiroshi Aoyama on the Gresini Honda, and Valencia Moto2 winner Karel Abraham on his private Ducati.

Superbike World Championship number five Cal Crutchlow will make his public debut on the Monster Energy Tech 3 Yamaha.

Interestingly, new MotoGP World Champion Jorge Lorenzo is using the number plate for the first time, likely to run the number full time in 2011.

Lorenzo’s current number one is a tribute to Wayne Rainey’s style used in the ’90s, however the word is that a Spanish paper is holding a contest to design his number for next season.

Stay tuned to MotoOnline.com.au for the official times from the test as well as a complete gallery of the test following day two.

Check out this free video clip of Rossi in action on the Ducati over at the official MotoGP website