Two minutes into the second half, disaster appeared to be headed for the Bruins. Instead, they won one of their best victories of the year.

David Pastrnak scored past Dustin Wolf 4:20 into overtime to complete the comeback as Boston erased a two-goal third-period deficit to beat Calgary 4-3 on Tuesday.

The Bruins will look to cap off the road trip with their third straight win on Thursday in Edmonton.

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The Bruins had a 9-4 lead in the first period, were outplayed and outrun, but escaped unscathed as the teams went into halftime tied 0-0.

They weren’t as lucky in the second period, as Calgary scored two goals in the first 1:21 of the period. Joe Sacco tried to reverse course, took advantage of his timeout and seemed to give his team a spark.

Former Flame Elias Lindholm, who was honored in the first period with a tribute video for his time in Calgary, scored his first goal in 12 games at 6:31 at midfield to make it 2-1.

Towards the end of the second he had a great view of another. With 3:21 left, Brad Marchand made a pass to him, giving Lindholm a small break as they entered the zone.

Boston’s increasing momentum would have exploded had Lindholm been able to score. But Dustin Wolf deflected his shot. That sparked a big swing when Ryan Lomborg took advantage of the fact that the Bruins defense was out of position 40 seconds later. His shot beat Jeremy Swayman and extended the Flames’ lead to two goals.

But the Bruins’ push continued in the third period. Morgan Geekie scored his second goal in as many games when he fired in the rebound of a shot from Andrew Peake, 4:14 into the third.

They tied the game less than three minutes later when Marchand fired Marc McLaughlin into the net. Wolf stopped his first shot, but McLaughlin followed it and fired in the rebound to make it 3-3.

Swayman made 20 saves to earn the victory.