The Canadiens, the No. 1 seed in the Eastern Conference, lead the best-of-seven, first-round series 3-1 and can wrap it up at home Thursday night.
The teams played evenly for much of the hard-hitting, fast-paced game until Brisebois scored on a power play with 42 seconds left in the second period.
Then Carey continued doing what he had done throughout the series: shut down Boston's mediocre offense.
Carey, the fifth overall pick in the 2005 draft, stopped 27 shots as he tries to become the third rookie goalie to lead the Canadiens to a Stanley Cup, after Ken Dryden and Patrick Roy. He stopped two solid bids in the second period even before Brisebois scored.
The Canadiens, who have trailed just once in winning 10 of 11 games against the Bruins this season, went ahead midway through a power play after Andrew Ference was sent off for tripping.
FLYERS 6, CAPITALS 3
In Philadelphia, Danny Briere's so-so first season in Philadelphia has turned sensational in the playoffs.
Briere has played more like the top player in the league than likely MVP Alex Ovechkin, scoring two more goals with an assist in Washington's win in Game 3 of the Eastern Conference first-round series Tuesday night.
No player has more postseason points the past three years than Briere. His four goals and two assists in the first three games have given the Flyers a 2-1 series lead.
Game 4 is Thursday night in Philadelphia.