If what the Boston Bruins showed in coming back to beat the Detroit Red Wings was the resolve of a champion, it certainly wasn't obvious to goaltender Tuukka Rask.

The Bruins erased a two-goal deficit in Game 4 to win 3-2 in overtime Thursday night at Joe Louis Arena and set up a chance to eliminate the Red Wings on Saturday. When they were behind and struggling, Rask didn't expect a switch to flip.

"It definitely didn't look like it at times," Rask said. "It was a bit ugly at times, but then we got our stuff together and got going. It's just one of those things that we have a lot of character in this room that once we get going, we can come [back] from a deficit. But it just has to happen."

It happened, thanks to goals from Torrey Krug, Milan Lucic and then the game-winner by Jarome Iginla on a triple deflection that Detroit goaltender Jonas Gustavsson was helpless to stop. The Bruins now need just one victory to set up an Atlantic Division final against the rival Montreal Canadiens.

"Tonight was our toughest one in the series. That's the way it's supposed to be, it usually is, as it goes on," said Iginla, whose goal came at the 13:32 mark of overtime. "Being up now, we want to close it out. There's no questions."

Bruins celebrate Game 4 win

Detroit Red Wings goalie Jonas Gustavsson skates away as the Boston Bruins celebrate their 3-2 overtime win in Game 4. (Carlos Osorio/The Associated Press)

One question Thursday night was how the Red Wings would benefit from the return of captain Henrik Zetterberg, who was playing his first game in two months after back surgery. The crowd of 20,066 cheered Zetterberg early and often and seemed to get even more of a spark from seeing him on the ice.

"Obviously having that emotional lift by getting their captain back was big for them I'm sure in the dressing room and you could hear it in the crowd, as well," Lucic said.

Detroit took a 1-0 lead 11 minutes in on a power-play goal by new father Niklas Kronwall, who was arguably the Red Wings' best player in Game 4. Kronwall's wife gave birth to a baby boy earlier in the day.

Pavel Datsyuk, whose wife gave birth to a baby girl Wednesday, made it 2-0 just 4:27 into the second on a play orchestrated by Kronwall, who was beaming at what life had to offer outside of this loss.

"Obviously it was a big day for me, a big day for me and my girl," Kronwall said. "It's something I'll never forget for sure. Rushed out of here, got there just in time to be there, and then just holding your son for the first time, it's a pretty special feeling."

Getting a surprise, last-minute start in place of the flu-ridden Jimmy Howard, Gustavsson wasn't tested much in the first and kept the Bruins off the board until Krug's goal 10:14 into the second.

Shutout bid gone, Gustavsson also lost his best chance to pick up his first win in the Stanley Cup playoffs in his debut when Lucic scored on Boston's first shot of the third period.

The overtime goal was just about impossible for the former Toronto Maple Leafs netminder to stop. Bruins defenceman Dougie Hamilton's shot went off Detroit forward Luke Glendening's stick, then Iginla, then Detroit defenceman Danny DeKeyser before going into the net.

"We just want to get pucks on net," Hamilton said. "We were doing a good job of that. It's pucks and bodies and things like that happen."

The goal was Iginla's sixth career game-winner in the playoffs and first since 2007.

"Pretty fortunate goal, fortunate bounce, an ugly one. But that seems to be how a lot of those are in OT," the former Calgary Flames captain said. "It felt pretty cool to be winning an OT game in the playoffs."

For the Bruins, winning Game 4 didn't happen in that instant but rather over a gradual period of time as they made this the ninth time a team erased a two-goal deficit in these playoffs.

"After they took the 2-0 lead, I thought we kind of settled down a little bit and started playing our game," Boston coach Claude Julien said.

From the other side, the Red Wings weren't able to keep theirs up. The boost from Zetterberg's return only lasted so long, and then the Bruins chipped away.

"I thought they got better as they game went on," Detroit coach Mike Babcock said. "As the game went on, we had more holes defensively."

Trying to patch those holes is one of the big jobs moving forward for the Red Wings as they try to stave off elimination.

The Bruins expect Detroit to be desperate Saturday at TD Garden and know they need to be prepared.

"We'll load up and we'll be ready," Iginla said. "We're not taking anything for granted. It's always that last game, historically, that's the toughest."

Gustavsson said he found out just before pre-game warm-ups that there was a chance he'd start in place of Howard, who led the Red Wings onto the ice.

The decision was made not long before puck drop as Babcock said of Howard: "Last second, he just couldn't go." ...

Daniel Alfredsson was scratched for the Red Wings as he continues to deal with back problems. Babcock said trainers told him that Alfredsson should be good to go for Saturday's Game 5 in Boston.

Todd Bertuzzi replaced Tomas Jurco in Detroit's lineup for his first post-season action, while Zetterberg bumped fellow Swede Joakim Andersson.