Just when it appeared the Blues were getting healthy by adding Colton Parayko and Sammy Blais back into the mix, the injury bug has bitten again.
The Blues announced on Wednesday they have placed forward Oskar Sundqvist on injured reserve with a lower-body injury.
Sundqvist has been a key piece in the Blues' lineup this season, scoring 11 goals and tallying nine assists in 44 games.
Forward Alex Steen also left the Blues' Tuesday night game in Calgary early with an undisclosed injury.
The Blues play next on Friday in Edmonton against the Oilers.