PITTSBURGH • The Pittsburgh Pirates can taste it now. It’s that opportunity to post their first postseason series victory in 34 years, excluding their one-game wild-card triumph last Tuesday.

Neil Walker probably would have been in the PNC Park stands Sunday, yelling his lungs out like most everybody else in the record, black-clad crowd of 40,489 if he wasn’t playing second base during the Pirates’ 5-3 win over the Cardinals in Game 3 of the National League division series.

Walker, a Pittsburgh native, said he had been there, doing that when he watched his beloved Steelers and Penguins take part in big regular-season games or postseason exercises that were just rumors to the Pirates for the last 20 or so years.

“I’ve lost my voice at Steelers and Penguins playoff games,” said Walker. “I’ll talk to my friends and family tonight and I’m hoping their voices are gone, too.”

The Pirates crowd might well have been a Steelers crowd Sunday. “It helped that the Steelers were on a bye week,” joked Walker. “But I think we’re getting the support that we deserve. We knew that it would come.”

On Sunday, Walker said the fans “brought it. And we felt it.”

Andrew McCutchen, the Pirates’ most valuable player candidate, was on base four times Sunday. And his double off Carlos Martinez ignited the Pirates’ eighth-inning rally, even though he was overly ambitious as a baserunner and got himself cut down at third base for the first out when Justin Morneau grounded to shortstop Pete Kozma and almost cut short the winning rally.

“(Kozma) was able to make a play and get me out,” said McCutchen, who still thought it was a good play. “We try to be aggressive and try to make the best decisions. And that was the best decision.

“I wasn’t able to get there, but I’m not necessarily worried about it because it didn’t matter.”

The howling crowd probably barely noticed a rare bad play by their star, they are so caught up in the frenzy.

“Because of what’s going on and what we’re doing, it’s a great feeling,” said McCutchen. “You don’t get this every single day.’’

McCutchen said he tries to look at the crowd every day before the game. “I see passion, the same thing we have on the field,” he said. “Fans hungry to see a winner, hungry to be a part of this. It’s the whole city.

“I try to soak it in as much as possible. For one, you’re living the dream, playing professional baseball. On top of that, we’re in the playoffs and we’re playing toward the World Series.

“This is something that you dream about and you’re living in the moment of it. It’s painting memories. They’re going to remember it forever, just as we are.

“Hopefully, they’re going to keep rocking that Roberto Clemente Bridge (that connects the park with downtown).”

Umpire Jim Joyce, who was in the middle of the field at second base on Sunday, said nearly an hour after the game, “My ears are still ringing.”

While the Cardinals were reluctant to include righthander Shelby Miller in their rotation for the series because Miller was 0-4 against the Pirates, Pittsburgh has shown no such reluctance to give righthander Charlie Morton the ball today.

Morton, who had Tommy John elbow surgery a year ago June, has been a punching bag for the Cardinals, losing six straight decisions to them, and he is 2-9 with a 6.52 earned run average against them overall. This season, he has allowed 12 runs in 13 2/3 innings against the Cardinals while losing twice with one no-decision.

In his most recent outing against them in St. Louis on Sept. 8, he was touched for five runs in 1 2/3 innings and left after suffering an injury to his left foot while backing up a base. One scout who was on hand for that game, said, “I hate to say this. But I think he quit.”

Morton said, “There are things that I’m going to take from it and I’m going to learn from, but I’m not trying to reinvent the wheel, because I had a couple of bad games against them.

“I have to be really careful about being too critical about certain things, because I think you lose the ability to be objective.”

But Morton, almost exclusively a sinkerball pitcher, said, “I would like to be able to have a pitch or develop something where I could be more effective against lefties.”

Indeed, lefthanded batters hit .314 (righthanders were at .222) against him, and Morton hit 13 of those hitters during the regular season.

Lefthanded-hitting Cardinals center fielder Jon Jay is eight for 16 against Morton. Carlos Beltran is six for 15. Yadier Molina is eight for 21. Allen Craig is nine for 18 and not available but the Cardinals should have plenty of firepower against Morton, who was 6-2 when he wasn’t facing the Cardinals this season.

Asked if he thought he was due for a better game against the Cardinals, he said, “Well, yeah. Hopefully.

“I’m excited. I want to contribute. Today was incredible, awesome. Would I have paid to watch this game? Absolutely.”

But asked how he would feel today, Morton smiled and said, “I don’t know. I’ve never done it before.”

The Pirates haven’t won the last game of a postseason series since the 1979 World Series. And that happened in Baltimore, just as did the last game of the 1971 World Series. These types of things don’t happen in Pittsburgh.

“I’m trying not to think about the outcome and what it could mean,” said the 29-year-old Morton, who is 30-49 for his career.

“I don’t have to put undue emphasis on the game tomorrow. From being a rational person, I realize how important tomorrow is,” he said. “But that’s not what I’m going to be thinking about, because it’s not going to get me anywhere.

“There’s no need for me to go home and think, ‘Oh, wow!’ I already know that. I’m going to home and eat some dinner and go to bed.”

When the Pirates awake today, their minds could be abuzz with the possibilities.

But Walker said that in spring training, even before the likes of Marlon Byrd and Morneau were acquired, “we certainly thought we were going to end up where we are — in the postseason. I don’t think many other people thought that. Maybe that’s why we don’t get too up, or too down. Because we expect to be here.”

This isn’t your father’s Pirates.

“The people who come here want to be here,” said McCutchen. “They want to be a part of something.

“In the past, it wasn’t like that.”

If Charlie Morton is worth his salt today, neither his past nor the Pirates’ will matter very much. They will be moving on. And that Clemente Bridge will be rockin’.

Derrick Goold covers the Cardinals and Major League Baseball for The Post-Dispatch. Follow him on Twitter at @dgoold or on Facebook at Facebook.com/BirdLandPD

Rick Hummel is a Cardinals beat writer for the St. Louis Post-Dispatch.