Blackhawks defenseman Brent Seabrook left Sunday's 4-2 win against the Flames with an upper-body injury and did not return.
Seabrook was hit from behind, falling into the boards then onto the ice after Calgary forward Rene Bourque hit him with 4:35 remaining in the first period.
Replays appeared to show Seabrook suffered a head injury, the extent of which is unknown.
It would be the third time in three years he has absorbed a hit to his head.
Brent Seabrook Takes Hit To Head