Former MotorGP star Jeremy McWilliams will replace injured Dan Kneen in the Mar-Train Yamaha team at this week's North West 200.
Manxman Kneen, 28, has been ruled out after breaking his arm in a mountain biking crash.
McWilliams, 51, will now have a busy week as he will also race a KMR Kawasaki in both supertwin races.
"It is nice to be able to step in for Dan and help the team out this week," said McWilliams.
"I'm keen to race the North West 200 with another professional outfit and my duties will be divided between SGS/KMR and Mar-Train during the week."
Mar-Train boss Tim Martin revealed that Kneen had undergone surgery but remains hopeful that the Manx rider will be fit for next month's Isle of Man TT.
"I am disappointed for Dan that this has happened, we have had a fantastic build-up to the event and I was confident he would have been very competitive," said Martin.
"At this late stage there were not many options available to us so we are very lucky that we have been able to bring in someone of Jeremy's pedigree.
"He was part of our test programme at the beginning of 2015 so has some knowledge of our bikes already."
Kneen said that he was "gutted" to miss out on the Northern Ireland meeting.
"I'm on my bike every day and wasn't doing anything different than usual, it was plain bad luck," Kneen added.
North West 200 practice begins on Tuesday with roads closing at 09:15 BST.