Michelin Ginetta GT4 Supercup front-runner Tom Hibbert is making a one-off appearance in the Ginetta GT5 Challenge this weekend at Croft.
It was initially planned for Supercup championship leader Tom Wrigley to take the drive with Rob Boston Racing, but business commitments have kept him away.
That opened the door for Hibbert to fill the void to make his Challenge debut, which competes on the BTCC support bill this weekend in place of the Supercup.
Running as a privateer entrant, Hibbert currently lies sixth in the standings after finishing every race bar one so far in the top ten, with a best of fourth at Donington Park.
He is one of three new names on the grid this weekend, with rallying ace Steve Perez making his debut, while Andrew Richardson makes a second outing of the year with family squad Richardson Racing.