World Superbike rider Jonathan Rea is set to replace the injured Casey Stoner for two rounds of the MotoGP series.
Northern Ireland star Rea will join the Repsol Honda team for Monday's test in Brno, and also for the two-day test in Aragon on 4 and 5 September.
Stoner is awaiting ankle surgery
and if, as expected, he is unable to return in time, Rea will replace him for the MotoGP rounds in Misano and Aragon.
Ten Kate Honda rider Rea is fifth in the World Superbike standings.
"I cannot take the smile off my race right now, this is a great opportunity for me," said the 25-year-old.
Cal Crutchlow became the first British rider to make the MotoGP podium in 12 years on Sunday
"I have sympathy for Casey and wish him all the best for his recovery.
"It is still a bit of a shock but I am happy Honda have put trust in me to do some testing mileage.
"I am under no illusions about how tough a class it is.
"The bike is an animal. A proper fire-breathing racing machine. I'm really looking forward to the challenge."
Rea, from Ballyclare in County Antrim, crashed out of the first race and finished seventh in the other at Sunday's Superbike World Championship round in Moscow.
The Ballyclare rider had been lying third in the first race when he crashed out and he fell off again in race two after a collision with Eugene Laverty, before remounting to take seventh.
Laverty took a creditable fourth position in Sunday's first race, before failing to finish race two.
Three rounds of the series remain.