Atlanta United's star striker Josef Martinez suffered an apparent arm injury in training on Wednesday.
The MLS club told the Atlanta Journal-Constitution that it was too early to tell the extent of the problem, after the newspaper reported Martinez collided with a teammate near the end of the practice session.
Martinez was on the ground for several minutes and left the field with his left arm in an air cast, according to multiple reports.
The 24-year-old has already scored five goals this season -- tied for the most in the league -- to go with his 19 from a year ago, when he finished fourth in MLS despite playing in just 20 games.
The news comes just as Atlanta is preparing to get new signing Ezequiel Barco back in action.
Barco, who became the most expensive signing in MLS history this winter, has yet to play after picking up a quad injury in preseason, but he returned to training on Tuesday before resting on a scheduled off day on Wednesday.
Winger Hector Villalba also missed training the past two days after picking up a knock in the second half of Atlanta's 5-0 win over LAFC on Saturday.
Atlanta United next faces New York City FC on Sunday.