Five-time Isle of Man TT winner Peter Hickman will contest the World Superbike round at Donington Park this weekend, replacing Markus Reiterberger at the works BMW team.
The Shaun Muir Racing-run factory outfit turned to Hickman after its regular rider Reiterberger came down with "a severe flu infection and high fever", which left him hospitalised ahead of the UK-based event.
"We are very sorry to hear that Markus is sick, feels unwell and is not fit to ride this weekend," team boss Shaun Muir said.
"I thank him for letting us know as soon as possible to give us time to find a replacement.
"Obviously it was very important to us to have an existing BMW rider as a replacement rider and Peter Hickman is an ideal choice for us. He is already riding the current bike and he agreed to join us very quickly.
"So we are very hopeful that he can do a good job for us at Donington Park and assist us with the development of the BMW S1000RR."
In addition to his road racing appearances, Hickman is a regular in the British Superbike series for the Smiths BMW team and sits eighth in the standings.
He was slated to race in French Superbikes at Magny-Cours this weekend but was permitted to join the WSBK grid instead.
Hickman previously contested a one-off round in the world championship at Donington back in 2012, finishing ninth in one race and retiring from the other.
"First of all, I'm sorry for Markus that he is unable to race at the weekend and I wish him a speedy recovery," Hickman said.
"At the same time, I am happy to step in and support the BMW Motorrad WorldSBK Team at Donington Park.
"I didn't have to think long when I got the call from Shaun Muir.
"It's quite some years ago when I did some races in this series. But I know the BMW S1000RR and the track at Donington Park very well, so I am confident that I can do a proper job for the BMW Motorrad WorldSBK Team."
Hickman will line up alongside Tom Sykes at Donington, the Yorkshireman having scored the BMW works team's first podium of the campaign last time out at Misano.
Hickman remains the fastest road racer in history, after obliterating the outright lap record at the TT with a 135.452mph lap.
He won the Superstock and opening Superbike races at this year's TT aboard the all-new S1000RR, while also tallying up his maiden success in the Supersport class on the Triumph 675 K2.