Gunnarsson is battling an upper-body injury and has seen limited action this season, appearing in 17 games with just 14:56 of ice time per contest. During that time, the 33-year-old has tallied just four points and one goal.
The 23-year-old defenseman Mikkola was drafted by the Blues in the fifth round of the 2015 NHL Draft. He has two goals and 6 assists in 26 games with the San Antonio Rampage this season.
Source: Fox Sports