Brad Marchand was clearly not at his best in the Bruins’ 6-5 shootout loss to the Ottawa Senators on Saturday. He had trouble handling the puck most of the afternoon and was slow to close on Josh Norris before the Senator scored the tying goal with 12 seconds left in regulation.

Still, when you sit the franchise’s all-time leader in overtime goals (21) for the extra session, as coach Joe Sacco did on Saturday, it raises a few eyebrows, no matter how the first 60 minutes of the game had gone.

But on Sunday, both coach and captain said that everything was copacetic between the two of them as Marchand took responsibility for his play.

“He’s going to make the decision on how he feels each guy is playing each night. I get it. I need to be better,” said Marchand after Sunday’s practice at Warrior Ice Arena.

“My details weren’t good enough. In a game like that they have to be spot on. Obviously, overtime is a big opportunity and you have to earn that right. It’s part of the game.”

It has not been the easiest season for the Bruins’ stars. Earlier in the season, former coach Jim Montgomery benched David Pastrnak for the entire third period in the B’s shutout win over Seattle on November 3 after Pastrnak had a nearly costly turnover at the end of the second period. Like Marchand, Pastrnak owned up to his mistake at the time.

Sacco did not say whether it was the last shift that made the decision for him or whether it was the overall body of work in the game. While he sat in OT, Marchand did see 19:20 of icetime in regulation and charged with two giveaways.

“It was just an in-game decision that we made, that I made. Marchy and I are on the same page, so I know that, knowing Marchy and the way he prepares and the way he works, he’ll be ready to go (Monday),” said Sacco. “He’s a true pro, so he’ll be ready to go. He’s dialed in, all the way, 100 percent. It was just an in-game decision that we made.”

The two were seen having a brief skate-and-chat prior to Sunday’s practice.

“We’re always in communication, Brad and I. Always. We have great communication,” said Sacco. “We talk about everything. Like I said, we’re on the same page. It’s just a decision we made, I made. With Marchy and the way he gets going, the way he gets himself ready, he’ll be ready to go (Monday).”

In general, Saturday’s game was a gut-punch loss, but the captain said there’s no use in letting it linger.

“Obviously we didn’t get the outcome that we should have had but there’s nothing you can do about it at this point. We have to rectify a couple of things and prepare for the next one. That’s all we can do,” said Marchand. “We’ve got to continue to build. There’s still a lot of time left here and you can’t get caught up with what’s happened.. You’ve got to look at the things we need to do better, work on that and get ready for the next one.”…

Sacco juggled his middle six lines, putting Matt Poitras between Marchand and Vinni Lettieri while Elias Lindhom centered Trent Frederic and Charlie Coyle.

Poitras was also slotted on the half wall on the second power play unit. He had not seen any PP time in his first two games back with Boston.

Sacco said he’s looking to get Poitras more icetime than the 10:32 he saw on Saturday.

“That’ll increase his minutes and his responsibility,” said Sacco of the PP time. “And he’s deserving of that right now. He’s played well. We’ve got to find a way to get him more minutes. We want to put him in situations to be successful obviously but he also has to learn there are certain situations in a game where he’s going to have to dig in. Maybe it’s a D-zone draw. But those are all learning experiences for him.”

The biggest challenge for a young player on the power play is not to automatically defer to other players, said Sacco.

Poitras has “to make sure he attacks off the elbow, get into a scoring zone and shoot the puck as well,” said Sacco. “I think as a young player, you’re looking for other options, you’re looking for other players and I think with Matty it’s important that he takes what’s given to him on the power play. Don’t force it. See what’s there and make you your play. Trust your instincts. That’s why we’re looking at giving him an opportunity there. But just don’t be the guy that’s looking to move it to someone else just for the sake of that.”…

Charlie McAvoy, out with a suspected hand/wrist injury, did not practice in Sunday and will be out for Monday’s matinee against the San Jose Sharks…

Pavel Zacha (maintenance) did not practice on Sunday but Sacco said that he’ll be play on Monday…

Cole Koepke, out since taking a head shot in the win over Tampa last Tuesday, remained off the ice.