Cassidy expects to match Miller with John-Michael Liles on Boston's third defensive pairing for Wednesday night's game, which is set for 7:30 p.m. ET at the Garden.
In a series that's become defined by the B's health woes on the point (the Bruins skated in Game 3 without four of their regular National Hockey League defensemen), it's expected that Colin Miller will be the one that steps back onto the ice and makes his return to the club's blue line.
Mike Hoffman scored two goals and Derick Brassard added another for the Senators.
Dion Phaneuf scored the overtime victor as the Ottawa Senators beat the Boston Bruins 4-3 Saturday to tie their Eastern Conference quarter-final series 1-1.
The Boston Bruins rallied from a 3-0 second period deficit only to fall to the Ottawa Senators 4-3 in overtime on Monday night at TD Garden in Boston.
Maple Leafs 4, Capitals 3 (2OT): Kasperi Kapanen scored his second goal of the game 11:53 into the second overtime and Frederik Andersen made 47 saves as Toronto evened the series 1-1.
Getzlaf's attempted pass across the high slot banked off Bouma's foot and somehow arched through the air and past Calgary's Brian Elliott for the Anaheim captain's second goal of the series. Bobby Ryan got the game-winning goal just five minutes into overtime on a power play.
It was the Senators' turn to play fast and loose with the lead after taking the Bruins to school and leading by three goals before four minutes had elapsed in the second period. Each of Boston's two goals was the result of poor puck management by the Senators, who on both occasions tried and failed to clear the puck numerous times before Boston took advantage of some tired defenders.
The Bruins outshot the Senators 10-9 in a scoreless first period and were ahead 23-18 on the shots clock heading into the third.
Karlsson's long pass was right to a breaking Hoffman, who deked and scored with one hand on his stick, slipping the puck just by Rask. That was followed 42 seconds later by Backes' slap shot after he broke through the Senators defense to swipe the puck and open the ice.
David Backes made a decision to get in on the fun a minute later when he scored and sent the Garden crowd into a frenzy with them being down just by a goal.
SIDNEY CROSBY and the defending champion Penguins have looked impressive in jumping out to a 2-0 lead against the Blue Jackets.
MacArthur tied it on the power play with his first goal since April 19, 2015.
Boston lost yet another defenseman as Adam McQuaid left midway through the first period with an upper-body injury and is day to day. He skated Sunday morning and could play Monday night.
Ottawa coach Guy Boucher, saying "rest is a weapon", kept his regulars off the ice Tuesday. The 26-year-old Swede has tremendous speed, stops and starts on a dime, controls the puck as if it were velcroed to his stick and can ignite the Ottawa offense - especially so on the power play - as effortlessly as pushing a button on an automatic auto starter.