Max Papis will stand in for Tony Stewart at this weekend's Watkins Glen NASCAR Sprint Cup round.
The 43-year-old Italian had already carried out a test for the team at the second road course on the Cup calendar before Stewart was sidelined by a broken leg sustained in a sprint car crash.
The race will mark Papis' first Cup appearance since a part-season with Germain Racing in 2010.
He has been a semi-regular stock car alongside sportscar drives since his Champ Car/IndyCar career came to an end.
Watkins Glen was the scene of Papis' best Cup result when he finished eighth in 2008.
Papis briefly raced in Formula 1 before crossing to America to race first sportscars, then in Champ Car in 1996. He contested seven grands prix for the Arrows team in '95.
It is not yet clear how long Stewart will be out of action for. There is now a Cup race every weekend until the end of the season in mid-November.
The three-time champion is currently 11th in the championship, but holds a wildcard entry for the Chase by virtue of his win at Dover. There are five more races until the Chase cut-off.