Bergeron answered 2:03 later at 16:09 to tie it 1-1, putting in a loose puck to the right of the crease after Pastrnak's pass hit the back of the net.
"I think it was a great effort, overall. We talked about taking it a game at a time, even when we got down 2-0 [in the series]. It's all about the next game. Here we are, and now it's all about Game 5," Bergeron said. "You have to build some momentum and confidence. We did that in Game 3 and tried to carry that into this afternoon."
Staal gave Carolina a 2-1 lead 33 seconds into the second period with a one-timer from the slot off a no-look pass from Nino Niederreiter behind the net.
DeBrusk tied it 2-2 on the power play at 18:44 during a scramble around the crease after Raanta could not find the puck. Carolina challenged for goalie interference, but the goal was upheld after video review.
"I didn't have it covered, but I felt like if you can take the goalie out his balance, and then score, it should be goalie interference," Raanta said. "I had a good conversation with the referee, and it is what it is. It's one of those where you just have to regroup and get back to work. It's frustrating."
Marchand put Boston ahead 3-2 43 seconds into the third on a 5-on-3 power play with a wrist shot from the high slot, and Pastrnak extended it to 4-2 at 5:41 after a cross-crease pass from Marchand off the face-off.
Marchand scored an empty-net goal with 35 seconds left for the 5-2 final.
NOTES: Boston was without defenseman Charlie McAvoy, who entered COVID-19 protocol before the game. Cassidy did not set a timetable on his return. … Marchand established a single-game postseason career high in points. Three Bruins have had more in a playoff game: Pastrnak (six in Game 2 of 2018 First Round), Rick Middleton (six in Game 4 of 1983 Division Final) and Phil Esposito (six in Game 1 of 1969 Quarterfinal). … The Hurricanes opened the scoring for the fourth straight game. The Colorado Avalanche (three games) are the only other team to score first in each game this postseason.