Pastrnak had two goals and an assist, Patrice Bergeron had a goal and an assist, and Tuukka Rask made 33 saves for the Bruins (5-1-1), who went 3-for-5 on the power play.
Pastrnak's second power-play goal of the game made it 3-3 with 3:05 left in the third period. Marchand's wrist shot from the high slot went wide and deflected off the end boards to Pastrnak, who spun and shot it in off Shattenkirk's stick.
"They're a good hockey club and we know what they bring to the table, obviously," said Bruins defenseman Torey Krug, who had two assists. "They haven't been happy with their starts lately, and they came out flying and they were the harder-working team for most of the game, I'd say. But we did a great job of coming back and getting a point out of it."
Pastrnak gave Boston a 1-0 lead with a power-play goal at 9:34 of the first period after receiving a pass in the left circle from Bergeron, who gathered the loose puck in the slot.
Point tied it 1-1 on a breakaway with 1.6 seconds remaining in the first. Point started the play behind his own net and left a drop pass for Victor Hedman before skating up ice. Hedman cleared the puck off the boards into the neutral zone to Yanni Gourde, who made a quick pass to Point as he split the defense before beating Rask to the glove side.