The injury was first reported by the Daily Herald newspaper in suburban Arlington Heights. The extent of the injury was not disclosed by the team.
Team spokesman Brandon Faber said Wednesday that team doctors are "monitoring" the injury.
A five-time all-star, Hossa signed a 12-year, US$62.8 million contract with the Blackhawks on July 1 after helping the Red Wings reach the Stanley Cup finals, where they lost to Pittsburgh. He led Detroit with 40 goals last season and was third with 71 points.
Hossa's arrival coincided with the departure of Blackhawks forward Martin Havlat, who signed with Minnesota. The Blackhawks hope Hossa will give even more punch to a team that reached the Western Conference finals last season.