Ottawa is looking to bounce back from their 4-0 loss against the Buffalo Sabres as they take on the Pittsburgh Penguins in their second game at home after returning from their world junior hockey championship road trip.
Anton Forsberg allowed four goals on 21 shots to Buffalo and has gone 0-2-1 in three straight games since returning from a lower-body injury.
Starter Linus Ullmark is week-to-week with a back injury which led to Merilainen getting recalled.
The 22-year-old rookie has appeared in four games this season, going 2-2 with a 3.10 goals-against average and a .884 save percentage.
Ottawa currently sits fifth in the Eastern Conference and will take on the Penguins on Hockey Night in Canada at 4 p.m. ET.