Krug's left ankle injury will keep him in a walking boot for the next three weeks, Joe Haggerty of NBC Sports Boston reports.

EDGE Analysis

GM Don Sweeney relayed that Krug's current issue isn't related to the injury that ended his playoff run last season, but it is affecting the same foot. With Krug set to miss time, Matt Grzelcyk (lower body) figures to see added opportunities out of the gate, while rookie Urho Vaakanainen could now end up making the Bruins' final roster in advance of Wednesday's season opener.