Morbidelli aggravated a pre-existing left knee injury on Tuesday in a training accident and has been ruled out of this weekend’s Assen round.
In his place comes American Gerloff, who was drafted in to replace Valentino Rossi in Valencia last year at the factory Yamaha star – only to ride on just the Friday as the nine-time grand prix world champion was cleared to ride from Saturday after passing a COVID test.
However, Gerloff’s performance in the mixed conditions on a bike and tyres he had no experience on impressed Yamaha management.
With no WSBK clash this weekend, Gerloff will finally get his shot at his MotoGP race debut at Assen on the two-year-old ‘A-spec’ M1 in SRT colours.
“I’m excited for the opportunity ahead, I’m not someone who runs away from a challenge, so I’m ready to get to the track,” Gerloff said.
“It’ll be a new circuit for me, I like trying new tracks, it looks fun, fast and flowing, and really suits my riding style.
“I’m looking forward to jumping on the Yamaha M1 again and twisting the throttle.
“We’ll see how things go, but I feel good and would like to thank Yamaha and the team for considering me.
“It won’t be easy, but I’m going to give it my best shot!”
Garrett Gerloff, GRT Yamaha WorldSBK Team
Photo by: Gold and Goose / Motorsport Images
Gerloff will be the first American rider to start a MotoGP race since the late Nicky Hayden stood in for the injured Dani Pedrosa at Honda in Australia back in 2016.
America’s last win in the top class of grand prix racing came at Assen back in 2011 courtesy of 2009 World Superbike champion Ben Spies, who was also riding a Yamaha.
Gerloff made his debut in WSBK with the GRT Yamaha satellite squad in 2020 having come through the MotoAmerica ranks.
Scoring three podiums last year, Gerloff added a fourth to his career tally in the opening round of the campaign at Aragon in May in the Superpole race for the GRT squad.
Gerloff has no prior experience of Assen, after last year’s WSBK round was cancelled due to COVID-19.