Plymouth Devils have signed former Scunthorpe rider Michael Palm Toft as a replacement for Kalle Katajisto, who was injured on his debut for the team.
Katajisto only joined the Devils last week, but has been ruled out for the rest of the season with a fractured jaw after crashing in his first race.
Toft, 23, from Denmark, will make his debut on Thursday against Ipswich.
"We needed to make a new signing as quickly as possible because we did not want to run with rider replacement," said Devils co-promoter Ashley Taylor.
"Michael has had some good scores in the past and will now have the opportunity to put himself in the shop window for the remainder of the season."
Katajisto was taken to hospital following his crash at Scunthorpe last Friday, but has since been discharged.
Taylor added: "It was unfortunate for Kalle, who must have had one of the shortest of debut meetings."