OTTAWA — Bruins interim coach Bruce Cassidy has not ruled out Colin Miller for Game 2 of the first-round playoff series against the Ottawa Senators. But as Miller noticeably limped through the lobby of the Bruins’ hotel, it at least seemed as though the defenseman would need some serious faith healing to see the ice Saturday.

So what’s the plan if Miller isn’t ready? Well, Cassidy said there are several possibilities, including using Joe Morrow, who has not played since Jan. 22.

“We have options. Our first plan is Joe Morrow, who has been with us all year and played some games for us. It would allow us to balance our left and right sticks,” said Cassidy. “After that, there’s the health of the guys who are out (Torey Krug and Brandon Carlo), are they going to be any better for (Saturday)? And then there are guys in Providence who’ve played well.

“It’s always been a next-man-up kind of mentality. When your sweater’s hanging up and you’re in the lineup, you’re expected to do your job. So whoever we choose, we expect they’ll be able to do it.”

Morrow, the last remaining piece of the Tyler Seguin trade, has been something of a forgotten man. He hasn’t played in almost three months. He has one assist and is minus-4 in 17 games. Morrow has a history of playing very well in his first game back in the lineup before leveling off subsequently, but he might have gathered a little too much rust on this layoff.

“We just think the guys we’ve put in have been better. It’s that simple,” said Cassidy when asked why Morrow hasn’t gotten any playing time. “In fairness to Joe, maybe the opportunity hasn’t been there as much as the other guys, but that’s the way it’s played out. And when he does get his chance, he’s going to have to prove that he can stay in the lineup.”

Neither Krug nor Carlo has met up with the team in Ottawa and, to the best of Cassidy’s knowledge, they had not yet begun skating in Boston.

If General Manager Don Sweeney dips down to Providence for a player, there are a couple options. AHL veteran Tommy Cross has had his most productive season in Providence (12 goals, 23 assists, plus-20 in 72 games). If the Bruins want to replicate Miller’s puck-moving skills, then there’s first-year pro Matt Grzelcyk (6 goals, 25 assists, plus-14 in 68 games).

It has been an up-and-down year for David Backes, but he had seemingly found his spot when he was placed on a line with Patrice Bergeron and Brad Marchand after Cassidy took over. The lineup changes caused by David Krejci’s unexpected absence threw him for a temporary loop, however. He started Game 1 against Ottawa on a line with Riley Nash and Drew Stafford, and then with Matt Beleskey.

“It was truthfully a little unsettling, I’m not going to lie,” said Backes about hearing the news Krejci wasn’t paying. “(I’ve been playing) with Bergy and March for the last 20-25 games, and before this game we had three or four days to practice together and talk out a lot of the game. Then a few minutes before the game it was ‘(David Pastrnak), you’re with Bergy and March. And Backs, you’re with Nasher and (Stafford). It was like ‘Crap, we have to adjust now …’

“It was a little bit tough. But sometimes when you get that kind of rattling surprise, like when you go down to five ‘D’, you simplify and worry more about each shift and each play. Sometimes that does focus you a bit more.”

While one of his first orders of business when he took over in February was to put Backes on the top line and pair Pastrnak with Krejci, Cassidy did not rule out putting Backes with Krejci if the centerman can return Saturday, while keeping Marchand, Bergeron and Pastrnak together.

“We’ll look at (Backes with Krejci). I didn’t love it during the season. I prefer the balance. But with the lower scoring series and the way Pasta plays with Marchie and Bergy, it’s something we will consider,” Cassidy said.

There was no update on Krejci’s status for Saturday.

Cassidy said Noel Acciari, who missed the regular-season finale and Game 1 because of an upper body injury, is close to returning and could play in Game 2.

The Bruins announced the signing of 6-foot-5, 194-pound Finnish forward Joona Koppanen, their fifth-round pick in 2016.