After the Reds mustered a single run in 12 2-3 frustrating innings against the 22-year-old Wacha, Jay Bruce said it was like facing a carbon copy of Cardinals ace Adam Wainwright, also lean and lanky and among the majors' best pitchers for several years.
On the rare occasions you get a pitch to your liking, Bruce said, you'd better not miss. ''It's been pretty well-documented about how good he is for the past year and a half,'' the Reds' Ryan Ludwick said. ''He got into situations and got out of them and kept runs off the board.''
Seeing a pitcher in consecutive starts should help opposing hitters. Better than seeing it on videotape, the repertoire, arm angle and velocity are all fresh in the mind.
It didn't help the Los Angeles Dodgers last fall when they didn't score a run in two NL championship series starts over 13 2-3 innings against Wacha. The Reds saw more curveballs and change-ups the second time around against Wacha.
''When his changeup is in the strike zone down, it's really tough,'' Ludwick said. ''He's added a baby cutter, like all these guys over there do. He's young, he's a competitor and he's tough to beat.''
Before the home opener, manager Mike Matheny scoffed off a question about the possibility Wacha might get too pumped up.
There was a lot more riding on the kid's shoulders last October, he reminded, when Wacha twice outpitched Clayton Kershaw and was picked the NL championship series MVP, and in the division series when he carried a no-hitter into the eighth of a do-or-die Game 4 in Pittsburgh.
Wacha waited out a rain delay of two hours and 40 minutes his first start this year before dominating in Cincinnati.
''There's things going on around the outside and yeah, he's going to see parades and horses and all kinds of stuff going on,'' Matheny said. ''He's done a real nice job, especially for a young pitcher, of understanding what he's got to do to get ready for the game.
''Don't be completely oblivious to it, but don't let it get in the way of what you need to do,'' he said.
Wacha has been on a fast track to stardom since the Cardinals drafted him 19th overall in 2012 out of Texas A&M, with a compensatory pick from Albert Pujols' free-agent departure for the Angels.
He made it to the majors less than a year later, the organization's quickest climber in more than a quarter-century. Warming up for October, he was one out shy of no-hitting the Nationals in his final start of the regular season.
Wacha joined a select group of pitchers to win four games in a single postseason, setting a major league rookie record with 33 strikeouts. This spring it was a given he'd join Wainwright, who's been in the top three for NL Cy Young award three times, at the top of the rotation.
Counting the postseason, Wacha hasn't allowed a run in six of his last 12 starts. Only twice, including Boston's clinching Game 6 victory, has he allowed more than two runs.
He expects that kind of result every time out.
''I wouldn't say surprising,'' Wacha said. ''I mean, that's my job to go out there and try to throw up zeroes every inning.''
''I just try to approach every game with the same mentality, go out there and attack the hitters. Try not to think too much about what kind of stage you're on, whether it's the postseason or opening day.''
It was 49 degrees for the Cardinals' opener. Again, a non-factor.
Wacha got the job done without his best stuff. The Reds had the leadoff man on base each of the first four innings only to be frustrated, wasting Billy Hamilton's double to open the game and coming up empty after the 8-9 hitters reached safely to start the third.
''I felt good out there but the command wasn't where I wanted it to be,'' Wacha said. ''I felt like I was throwing out of the stretch the whole game.''
Inducing a pair of double-play balls helped Wacha keep the Reds in his pocket the second time around.
''He did a nice job of managing the baserunners,'' Cincinnati manager Bryan Price said. ''He doesn't typically make a lot of mistakes. He's just good quality.''