He signed a one-year contract with the Blues in the offseason after Ville Husso signed with the Detroit Red Wings.
"We've got a lot of games coming up. We don't want to overuse one goalie, and Greiss has been sitting and is ready to go," Blues Head Coach Craig Berube said. "He's worked extremely hard in practice, and he's been around, played a long time. He understands (how to be ready)."
Monday's game will bring about plenty of other lineup changes for the Blues. The team has already been without Pavel Buchnevich due to an undisclosed injury, but now the team also won't have Brandon Saad available due to an upper-body injury sustained Saturday. Berube said Saad is day-to-day.
The absence of Saad means Logan Brown will be back in the lineup after sustaining an injury in the preseason. Prior to the injury, Brown led the team with four goals in three preseason contests.
"I was feeling good," Brown said of the preseason. "I'm still feeling good, so let's back to that in the regular season now."