Callahan, who is considered day-to-day, suffered the injury Monday night against the New Jersey Devils, but was not forced to leave the game. Newly acquired John Scott will take his place in the lineup.
Callahan has 25 goals this season, second-most on the team.
It's something that you don't really envision starting this way, but when you put the work in you don't feel like it's unwarranted. You definitely don't envision it unfolding this way, but you do think you can be successful at this level.
— Senators goalie Andrew Hammond, who defeated the Jets on Wednesday to improve to 6-0-1 since making his first NHL start on Feb. 18