OTTAWA -- Bruce Cassidy will be making some lineup changes headed into the Bruins' do-or-die Game 5 against the Senators, and the most significant is that Ryan Spooner won’t be playing after a largely ineffective first four games in the series.

Cassidy said Spooner “was less than 100 percent” due to an unspecified injury, but that it’s something he could have played through under normal circumstances.

Rookie Sean Kuraly will be back in the lineup after doing a pretty good job filling in for Noel Acciari earlier in the series, and he’ll center a young, more inexperienced fourth line that includes Frank Vatrano and Tim Schaller.

“[Spooner] could play. This is more about what Sean brings right now,” said Cassidy. “Clearly Ryan does some very good things for us, but we just made a decision that Sean, as a center iceman, will bring us some good qualities as well. So we had to make that decision.”

Clearly Spooner hasn’t done enough during five-on-five play to justify keeping him in the lineup for power-play responsibilities, and he wasn't making enough of an offensive impact with just two shots on net in four games.

Otherwise most of the group is the same. There's still no sign of the injured Torey Krug, Brandon Carlo or Adam McQuaid as the Bruins, who trail the best-of-seven series 3-1, play what could be their final game of the year.

Here are the projected Bruins line combos and D-pairings based on morning skate:
Morrow-K Miller
Liles-C Miller