PITTSBURGH — The time is now.

The Red Wings have an opportunity to take an insurmountable 3-0 series in the Stanley Cup finals against the Penguins.

But on Wednesday, the scenery is a little different.

For Games 3 and 4, the series shifts to the Steel City’s Mellon Arena. It’s the oldest arena in the league, beating Joe Louis Arena by 18 years.

And Mellon wasn’t even originally built for hockey. Formally known as the Civic Arena, it boasts the largest retractable, stainless steel dome roof in the world. The arena was originally built for the Pittsburgh Civic Light Opera, so that audiences could enjoy musical theater … under the stars.

Now, the stars are inside. And the almost half-century old building is the Penguins’ secret weapon.

Mellon was sold out every game this season. Over 13,000 fans packed the arena to watch Games 1 and 2 of the final on the Jumbotron. And the Pens haven’t lost in front of their fans since February 24.

“In the playoffs they’ve made such a difference,” Pens defenseman Ryan Whitney said. “It can get loud in here. We get a couple shots and we can really get some momentum going through the crowd. …

“If we can the first goal, this place will be rockin’. And hopefully we can go from there.”

Wings coach Mike Babcock knows how significant the shift in venue can be. In 2003, Babcock’s Anaheim Mighty Ducks were shutout twice in New Jersey before tying the series at the Arrowhead Pond.

It’s something Babcock has been reminded of since the Red Wings have been up 2-0 in every series in the 2008 playoffs.

“Being through that in the past helps me understand what they're going through, and yet helps me understand what we need to do,” Babcock said.

But “The Igloo” is home — not only for the Pens, but also for the most pivotal game of the series. Only two teams have rallied from 3-0 deficits, and just one in the finals — the 1942 Toronto Maple Leafs came back to beat, coincidentally, the Red Wings.

“We think it’s a tough building to play in,” Pens defenseman Rob Scuderi said. “And we hope to take advantage of that. If they’re the same crowd they’ve been up to this point, I like our chances.”

SYDOR IN, LETANG OUT: Veteran defenseman Darryl Sydor will replace rookie Kris Letang in Pittsburgh’s lineup for Game 3. He will be paired with Whitney, who will move to the right side.

Sydor instantly brings experience to Pens’ lineup — the 36-year-old has played in 151 playoffs games, winning Stanley Cups in Dallas and Tampa Bay.

“(We) certainly could use experience on the ice and even on the bench, communicate really well with the players,” Pens coach Michel Therrien said. “So I'm excited for him to finally get a chance to play in these playoffs.”

Sydor played in 74 regular-season games, but has not played since March 31.

“He’s been a great teammate throughout this whole thing,” Whitney said. “He had every reason in the world to sulk, or be upset, and he hasn’t at all. He’s practiced every day and really been there for guys — really supporting this team trying to win a Cup. So it’s good that he’s back in tonight.”

NOTES: When asked whether he minded the Henrik Zetterberg-Sidney Crosby matchup, Therrien responded: “I don't mind that matchup against Zetterberg and Datsyuk. Crosby is one of the best players, if not the best player, in the league. So you think I mind? And he likes challenge.” … Babcock met with league officials today, saying most of the meeting had to do with blows to the head, but would not go into further detail. But it sounded like a one-sided conversation. “What I liked about the meeting today is they weren't very much interested in listening to me,” Babcock said.