Nicky Hayden will make a one-off MotoGP return in Aragon this weekend as a replacement for the injured Jack Miller.
Hayden, 35, announced his retirement from the premier class last October, opting to ply his trade in the World Superbike Championship for Honda.
The 2006 MotoGP champion will be aboard the Honda RC213V at the Motorland Aragon track in the absence of Miller, who is recovering from fractures to his right arm sustained at the Red Bull Ring in Austria last month.
Australian Miller was ruled out for round 14 in Spain after it was revealed that he raced with two fractures in his right hand in San Marino and at Silverstone.
"First of all I want to wish Jack a speedy recovery. He is a buddy of mine and he is a rider I believe in a lot, so I hope he can get healthy as quickly as possible to show the high potential we all know he has got." said Hayden.
"He just needs to get his body right so he can perform. This is an unusual experience for me because I've never been a stand-in rider before.
"But I have a good relationship with Honda and when the idea first came up they were behind it and Ten Kate gave me their blessing, so it is nice to go and help out another Honda team.
"For me it's just a chance to go and have fun. I'd probably be riding motorbikes anyway and I would definitely be watching the race on TV, so I might as well show up and have some fun.
"I know MotoGP is not a place that's always easy to have fun because the level is so high but I've got a lot to learn and it won't be a walk in the park. I haven't ridden the bike and there are different tyres and electronics but I've got a lot of experience and I get another shot at MotoGP, which is great for me personally."