Koepke (upper body) was placed on injured reserve Saturday, per the NHL media site.
Boston activated Mark Kastelic (upper body) from the IR list in a corresponding move. Koepke missed Saturday's 6-5 shootout loss to Ottawa and won't be eligible for Monday's matchup versus San Jose. He has seven goals, 12 points, 99 hits and 44 shots on net in 44 appearances this season.