Krug skated off the ice with 8:58 left on the clock in the first period.
On Saturday, Blues Head Coach Craig Berube said Krug would be out for "some time."
"It's unfortunate," Berube said. "We've got to try to do what we can do, control what we can do, guys have to go in there and guys have to do the job. (Krug) has ran that power play now now for quite some time and it's been very successful. He's not around, so somebody else has got to come in and do the job."
The Blues were already playing without defensemen Nick Leddy (upper-body) and Robert Bortuzzo (upper-body) due to injuries. Both players joined the team late in Saturday's practice.
