Pittsburgh Penguins left wing Chris Kunitz (14) is congratulated by teammates after his goal against the Boston Bruins during the second period in Game 3 of the NHL hockey Stanley Cup playoffs Eastern Conference finals, in Boston on Wednesday, June 5, 2013.

BOSTON - Patrice Bergeron scored 15:19 into the second overtime to lead the Boston Bruins to a 2-1 victory over the Pittsburgh Penguins and a 3-0 series lead in the Eastern Conference finals on Wednesday night.

The victory put Boston in control of the best-of-seven series and a chance to advance to the Stanley Cup finals in Game 4 on Friday night at home.

Tuukka Rask stopped 53 shots for the Bruins.

"It was a battle. They played hard all night," Bergeron said. "It was a tough game, we found a way."

Tomas Vokoun made 38 saves for the Penguins one game after he was yanked from the net after giving up three quick goals in the first period.

David Krejci also scored for Boston in the first period. He leads the playoffs in scoring with nine goals and 12 assists.

Chris Kunitz scored Pittsburgh's only goal in the second.

That left it 1-1 after two periods, and it stayed that way through two more. But 4:41 before the second overtime would expire, Brad Marchand grabbed the puck along the left-wing boards and centered it, where Bergeron redirected it past Vokoun and into the net.

"That was a great play by March," Bergeron said. "I think the speed of March and, I guess, our chemistry. I just was trying to get open going to the net, and he found my stick."

That set off a celebration in Boston - the first for the Bruins at home this series after they won the first two games of the series in Pittsburgh 3-0 and 6-1. It is the first time all season that Pittsburgh has lost three consecutive games.

The good news for the Penguins: The last of three teams to blow a 3-0 lead in an NHL playoff series was Boston, which lost four in a row to Philadelphia in the 2010 Eastern Conference semifinals.

After two Boston blowouts, the Penguins matched the Bruins and even outshot them 39-25 in regulation - including a third period in which Pittsburgh held a 14-4 advantage despite two Boston power plays. The Bruins didn't muster a shot in the final 7 1/2 minutes of regulation.

But the Bruins had the better chances in overtime, including Nathan Horton's breakaway that Vokoun turned aside just 2:21 in, and another shot by Horton that went off the right post with 12:25 on the clock.

Pittsburgh forced Rask to make a save with 5 minutes left in the first OT, when Craig Adams tried to poke home a rebound.

"That surprise me? No," Bergeron said of Rask's play. "He is doing everything now. He is awesome."

The Bruins scored just 102 seconds into the game when Krejci circled around the net and took a slap shot that caromed in off Pittsburgh defenseman Matt Niskanen. But the Penguins tied it in the second - the first time in the series, other than 0-0, that they have been even - when Kunitz one-timed a pass from Paul Martin over Rask's right shoulder.

Pittsburgh went 0-for-6 on power plays. Boston was 0-for-5.

NOTES: Boston is 4-1 in playoff overtime this year. Pittsburgh is 2-2. ... Bruins F Gregory Campbell blocked a shot with his midsection on a power play late in the second period. He remained on the ice for a few seconds before struggling to his feet, then limped around for more than 30 seconds before Boston could clear the zone and he could get off the ice. Fans chanted his name. ... The Bruins honored Richard "Dic" Donohue as an honorary banner captain before the game. Donohue is a transit police officer who was shot during the Boston Marathon bomber manhunt. ... Penguins F Jarome Iginla, a key trade-deadline acquisition who turned down a deal to the Bruins, was dropped to the third line. ... Krejci has 29 goals and 39 assists for 68 points in 74 career playoff games. ... Pittsburgh had won its last six games in Boston, all in the regular season.