Toronto coach Mike Babcock said Sunday that he is making contingency plans to fill Kadri's spot in the lineup.
"Obviously I've got a couple of options in (Patrick) Marleau and (William) Nylander, so we'll work that out and decide what's best so we can get back to playing like we did in Game 1," Babcock said.
Marleau and Nylander, each of whom usually plays on the wing, saw time at center when the Maple Leafs and Bruins played in the first round last season, when Kadri was suspended for three games for an illegal hit on Boston's Tommy Wingels during Game 1.