BOSTON – The Bruins will be minus another member of their defensemen corps for at least the rest of Sunday night’s game as Connor Clifton exited in the first period with an upper-body injury.

Clifton played seven shifts and 5:52 of ice time with one shot attempt and two hits in the Sunday night Atlantic Division tilt with the Buffalo Sabres at TD Garden, and never came out for the second period at all.

The Bruins are already down both Torey Krug (upper body) and Charlie McAvoy (upper body) to injuries after both were taken out in Monday night’s win over the Washington Capitals, and neither player is expected to return for Tuesday night’s game with the New Jersey Devils.

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Krug skated on his own ahead of Bruins morning skate at Warrior Arena on Sunday, but McAvoy did not take the ice at all with the B’s hoping he’d be ready to skate in the next couple of days. As it is, both Krug and McAvoy are day-to-day while Bruce Cassidy said that he doesn't think Clifton's injury is serious postgame.

“He had an upper body injury. He’ll get checked out,” said Bruce Cassidy. “We’ll see how it is. I don’t think it’s [serious] but we’ll see. It’s a testament to [Zdeno Chara] and [Brandon] Carlo…a lot of minutes, tough minutes.”

Clifton has two goals in 29 games this season and has been a constant as a bottom-pairing defenseman for the Black and Gold. He even got into it physically with Sam Reinhart during Boston’s win in Buffalo on Friday night.