Casey Stoner is to leave Honda and work with Ducati as a test rider and brand ambassador from 2016. Two press releases, one from Honda and one from Ducati, today confirmed the rumor which had emerged at Valencia during the race weekend, and especially after the test. Honda thanked Stoner for five years of collaboration, including two years of racing, during which he won fifteen races and a MotoGP championship. After his retirement, at the end of 2012, Stoner continued as a test rider for HRC, but rode only sporadically, no more than a couple of days a year.

This, it appears, seems to have been the trigger for Stoner to make the switch to Ducati as a test rider. The Australian had always retained good ties with the Italian factory, and the arrival of Gigi Dall'Igna as the head of Ducati Corse made a return to Ducati even more attractive. Stoner knows Dall'Igna well from his time racing an Aprilia in 125s and 250s, a period in which he finished as runner up in the 250 championship to Dani Pedrosa. As the only rider to have brought Ducati a MotoGP title, and after five long years since their last victory in the premier class - Stoner also being the last race winner on a Ducati - the Bologna factory have a lot of good reasons to sign the Australian. Stoner will no doubt also be well acquainted with the situation at Ducati through his good friend Chaz Davies, factory rider for Ducati's World Superbike team.

Though Stoner has made it clear he has no intention of returning to racing full time, he still enjoys riding MotoGP machines, and the chance to ride a Desmosedici more often than just two or three days a year will have been reason enough for him to leave. The Australian reportedly felt underutilized at HRC, due in part to the role of Marc Marquez as lead rider. According to German-language website Speedweek, Marquez felt threatened by Stoner's presence as a test rider, and criticized the input Stoner had given on the project. Marquez claimed he had to test everything Stoner had already tested, to check Stoner's feedback. HRC sources also let slip that Stoner had been over a second off the pace during his most recent test, at Sepang at the beginning of 2015, and so the combination of resistance from Marquez and slow times had made HRC reluctant to use the Australian. Stoner's lack of pace was also a factor in HRC not asking Stoner to replace Dani Pedrosa when the Spaniard was out with injury, something which Stoner had taken badly.

There are no such qualms at Ducati. Though the Desmosedici GP15 is a huge step forward over the previous bikes from the Bologna factory, the machine still has several weaknesses, mostly concentrated in the chassis. Andrea Iannone has been a revelation in 2015, maturing into a real threat for the podium every race, while Andrea Dovizioso is a solid and technically sound rider capable of giving very clear feedback. They still need help, though, to turn the GP16 from a contender into a winner, and this is precisely where Stoner should be able to help, especially alongside Michele Pirro, who has proven to be a talented and very quick test rider.

For the moment, it seems that Stoner will mainly concentrate on private tests, not riding in any of the official 2016 preseason tests at Sepang, Phillip Island or Qatar. However, as Stoner gets some miles under his belt, and particularly once he picks up some of the speed being away from racing tends to remove, the Australian could well make appearances at public tests, and possibly even as a wildcard at races. For 2016, the earliest Stoner could race would be the Mugello round on 22nd May, but a much more likely scenario would be Stoner racing at Phillip Island on 23rd October. That would also help boost attendance at the Phillip Island round, which has fallen by up to 20,000 since Stoner's retirement, the crowd on race day being just over 35,000.

One place where fans can be sure of seeing Casey Stoner on track is during next year's World Ducati Week at Misano, due to take place from 1st - 3rd July.

Below are the two press releases from Ducati and Honda respectively:

Casey Stoner to return to Ducati as brand ambassador and test rider

Ducati Corse is delighted to announce that two-time MotoGP World Champion Casey Stoner will return to the Italian manufacturer next year in the role of brand ambassador and test rider.

Casey Stoner won the 2007 MotoGP World Championship on the Ducati Desmosedici GP with ten wins in eighteen races, results that also helped the Italian manufacturer to clinch the Constructors’ title. Between 2007 and 2010, Casey won a total of 23 races for Ducati.

The 30-year-old Australian from Southport (Queensland), who is widely considered to be one of the fastest and most talented riders ever, will become brand ambassador for the Bologna-based manufacturer and, as part of the agreement, will appear at the 2016 edition of World Ducati Week, scheduled to run from July 1-3. He will also take part in a selected number of MotoGP tests for the Ducati Team next year.

Casey Stoner: “It’s been a great journey with HRC over the last five years, winning the World Championship in 2011 was obviously a high point and I've made many friends and formed lasting relationships along the way. For 2016 I am very excited to announce that I will again be joining the Ducati team! I have so many great memories working with the people and the brand of Ducati and the opportunity to work with them again is something very special. Gigi Dall'Igna has brought with him a new approach and I'm looking forward to assisting the team, Andrea Dovizioso and Andrea Iannone however I can. The Ducati brand and the Ducati fans have been such a big part of my career and my life, so it will be really great to reunite the relationship and start another chapter with this iconic brand.”

Claudio Domenicali (CEO Ducati Motor Holding): “Stoner has always remained in the hearts of all the Ducatisti and I am really pleased that he has decided to come back to our family. Casey has an extraordinary talent and with his experience he will be able to make an important contribution for Gigi and the two Andreas in the development of the Desmosedici MotoGP bike. His presence at WDW 2016 will be a special gift for all the Ducati fans and enthusiasts, who will finally have the opportunity to catch up once again with this great champion who brought the 2007 world title to Borgo Panigale and who won numerous GP races with the Desmosedici GP.”

Honda bid a fond farewell to Casey Stoner

After a five year collaboration with Honda Racing Corporation, Casey Stoner will part ways with the Japanese manufacturer at the end of 2015.

Casey joined the factory squad – the Repsol Honda Team – in 2011 and adapted immediately to the RC212V bike winning ten races, and taking one 2nd place and five 3rd places. His victory in the Australian Grand Prix was his fifth in succession at his home race where he clinched the World Championship, Honda’s first since 2006.

Throughout his career with Honda, Casey has achieved a total of 15 victories (10 x 2011, 5 x 2012), 2 second positions (1 x 2011, 1 x 2012), 9 third positions (5 x 2011, 4 x 2012) in total 26 podiums. In addition to 17 pole positions (12 x 2011, 5 x 2012) and 9 fastest race laps (7 x 2011, 2 x 2012). He also celebrated a second place finish and one pole position aboard the satellite LCR Honda in 2006.

Honda Racing Corporation would like to thank Casey for all that he achieved during his time at Honda, and wish him and his family the very best for the future.

Shuhei Nakamoto

HRC Executive Vice President

"We have great memories of Casey’s time with Honda. From the moment he arrived in 2011 in the Repsol Honda Team we had a very close relationship and we always enjoyed speaking to him about racing and technical matters. Of course his Championship win in 2011 was a very special moment for us and a highlight of my career. Even after his racing days were over, I enjoyed attending his tests to take with him and spend time together. We would like to thank him for everything he gave to us over the past five years and send our best wishes to him and his family."