More has been revealed about an upper-body injury that forced Aaron Ekblad to miss North America's World Cup game against Russia on Monday.

The defenseman is reportedly suffering from a "mild concussion," according to Craig Custance of ESPN.

The injury was reportedly sustained on a hit from Finland's Leo Komarov in North America's first game of the tournament.

Ekblad's availability going forward is yet to be determined, and North America general manager Peter Chiarelli referred to him as "day-to-day" during the second intermission of Monday's game.