PITTSBURGH — Michael Wacha heard the chants. Then again, when 40,000 people clad in black scream your name relentlessly for the better part of three hours, it’s kind of hard to miss.
The goal was to rattle the St. Louis rookie, remind him that 22-year-old pitchers aren’t built to withstand the pressure of an elimination game.
One problem. Wacha doesn’t really do rattled. He doesn’t do pressure, either. The louder PNC Park grew, the more unhittable Wacha became.
Wacha took a no-hit bid into the eighth inning and the Cardinals showed off their October poise, edging the Pirates, 2-1, Monday afternoon to force a winner-take-all Game 5 in the NL Division Series.
‘‘I kind of like it,’’ Wacha said. ‘‘It kind of gives me adrenaline. I kind of use it in my favor.’’
And the Pittsburgh Pirates — not to mention anyone else he might face in the postseason — ‘‘kind of’’ need to get used to it.
St. Louis is 7-1 over the last three years with its season on the line.
Wacha nearly no-hit the Nationals in his last start on Sept. 24, surrendering only an infield single by Ryan Zimmerman with two outs in the ninth.
Pittsburgh’s Pedro Alvarez hit his third home run of the series, connecting with one out in the eighth for the Pirates’ only hit. It wasn’t enough for the Pirates to advance to the NL Championship Series for the first time in 21 years.
Wacha walked two and struck out nine before giving way to the bullpen in the eighth.
Matt Holliday’s two-run homer off Charlie Morton in the sixth was all the offense required on a day the Cardinals tossed the first one-hitter in the club’s lengthy postseason history.
Trevor Rosenthal worked around a two-out walk in the ninth, retiring Andrew McCutchen on a pop to shallow center field for his first postseason save.
‘‘It was a good pitch for him,’’ McCutchen said. ‘‘I wish it got a little more of the barrel. It would have been a great story.’’
The Cardinals finished with only three hits. Holliday got two of them, including his homer in the sixth after Morton walked big-hitting Carlos Beltran to start the inning.
‘‘You could go back and look at pitches over and over again and second-guess yourself,’’ Morton said. ‘‘I don’t know where that pitch was. It was outer third somewhere, thigh down, and he went out and got it, he’s strong.’’
Wacha, barely a year removed from a standout career at Texas A&M, didn’t permit a runner until walking Russell Martin leading off the sixth.
Alvarez got the fans at PNC Park roaring with his homer, and Wacha followed by walking Martin on four pitches. Carlos Martinez relieved and Gold Glove catcher Yadier Molina made a key play, throwing out pinch-runner Josh Harrison after a botched hit and run.
Martinez struck out Jose Tabata to end the eighth, and Rosenthal took over to begin the ninth. Neil Walker drew a two-out walk before McCutchen made the final out.
‘‘That’s what it’s all about,’’ Rosenthal said. ‘‘That’s what you dream of, you dream of two outs in the bottom of the ninth, you know . . . bases loaded, the best hitter up, and getting out of that spot.’’