World Superbike rider Michael van der Mark will replace Valentino Rossi for Movistar Yamaha at the Aragon MotoGP as the Italian continues to recover from a broken leg.
Rossi missed his home race at Misano on Sunday after suffering a fractured tibia and fibula in a training crash, an injury that is likely to rule him out of world championship title contention this season.
The veteran recovered from a similar break in just 40 days to race again in 2010 and could yet feature in the Grand Prix of Japan at Motegi next month.
For now, though, Van der Mark will make the switch from Yamaha's Superbike team to represent the manufacturer in MotoGP for the first time.
"I'm excited to be given the opportunity to ride the YZR-M1 at the Aragon MotoGP round," he said in a statement.
"I've never ridden a MotoGP bike before, so this will be a completely new experience for me.
"I'm very curious to see what it feels like to ride on such a machine.
"I realise that it won't be easy going straight into an official practice session without any prior testing. Nevertheless, I'm very grateful to Yamaha for the opportunity.
"I'm sure it will be a great learning experience."