ST. LOUIS -- Game 162 of the Cardinals' season could have been appropriately described as inconsequential, given that, one night earlier, the Cardinals had sealed their place in the postseason.

For Marc Rzepczynski, however, that night could come to be the turning point, the defining moment of what has been an up-and-down 2012 campaign.

The appearance was brief -- two batters, 11 pitches -- but it ended with a strikeout of Cincinnati's Joey Votto. And with it, Rzepczynski gave an indication that he might just be back.

"I felt a little more drama than I had in a long time," Rzepczynski said. "That helped build the momentum into [Friday's Wild Card game]. It was definitely a confidence booster."

Rzepczynski was in need of a boost, having been called upon only sparingly in September. The transition was slow, but manager Mike Matheny began summoning rookie left-hander Sam Freeman more often in the critical lefty-on-lefty matchup spots that had been Rzepczynski's earlier in the year.

That left Rzepczynski to log only four innings in eight appearances.

"Being a left-hander, you always wonder what the right situation is," Rzepczynski said. "Sometimes I thought maybe I'd have a chance to go in, but he turned to Freeman, who did a great job for us. When that phone rang I would just be ready in case it was me."

Wild Card vs. Nationals

From here on out, it will be Rzepczynski, who, as announced on Saturday, is the Cardinals' left-hander of choice this postseason. Freeman was left off the roster, making Rzepczynski the lone lefty in the 'pen.

The experience factor -- Rzepczynski made 12 playoff appearances with St. Louis in 2011 -- played a large role in the Cardinals' decision to stick behind him this month. So, too, did his outings in the team's most recent two games.

Having wrapped up the regular season on a positive note, Rzepczynski opened the postseason with another. Called upon to get out of a jam in the seventh inning of Friday's Wild Card game, Rzepczynski allowed a hit before rebounding to retire switch-hitter Chipper Jones, who, at the time, represented the tying run.

"I really believe he peaked at the right time," Matheny said. "He continued to have better and better outings. ... Really the message we have had for him is, 'We know that you're going to be able to perform for us when we get into that tight spot.' Last night he did, and we are going to continue to need him and we are going to continue to use him."

Critical contributions in the postseason would overshadow the inconsistencies that plagued Rzepczynski during the regular season. After posting a 1.98 ERA through his first 17 appearances of the season, Rzepczynski lost feeling for his slider and faith in his fastball, which, because he was trying to throw harder to compensate for issues with the slider, was often flat and right down the middle.

Over his next 20 outings, Rzepczynski was knocked around for 25 hits, 15 earned runs and four homers. By the time July arrived, his ERA sat at 5.86. No longer was he the steady left-handed setup man that the Cardinals had envisioned.

"For a six-week span," Rzepczynski said, "I don't think I had any idea where the ball was going."

As June closed, he made a deliberate effort to regroup.

"I think once July hit, it was just trying to put those two months behind me," Rzepczynski said. "It seems like when July comes, I always get locked in. I just feel like July is always a key turning point because it's the start of the second half of the year. I feel like since July, I have thrown the ball where I wanted to."

The numbers would back that up, even if his usage did wane late in the year.

Rzepczynski made 33 appearances over the final three months. He was scored upon in just three of them and limited batters to a .186 batting average. Twelve of those outings were at least one inning in length, and he allowed just one home run.

He closed the year with similar success against right-handed and left-handed batters, and he takes a scoreless appearance streak of nine games into the National League Division Series.

"We need him to believe in himself," Matheny said. "He knows now that he's our guy. He had some ups and downs this season, but he's too good of a pitcher for him to ever doubt how much he means to our club."