In the span of 20 seventh-inning pitches, however, the outing unraveled. Two singles, a cutter crushed for a three-run homer, two more doubles and a walk produced five Chicago runs and unceremoniously chased Wacha. It also set the stage for the Cubs' division-clinching celebration.
"It happened in a hurry, and it was unfortunate because he had special stuff today," manager Mike Matheny said. "Those first six [innings] were probably as good as we've seen from anybody this year."
And that's what Matheny hopes Wacha can hang onto.
Six months ago, Wacha wrapped up a reassuring Spring Training performance still knowing that plenty of questions lingered. Could his shoulder hold up? Would his reworked offseason workout regimen make a difference? And could he keep a rotation spot from season start to season end?
Though there were temporary dips in effectiveness along the way, Wacha answered each in the affirmative.
"I'm very happy with the way I feel, for sure," Wacha said after Wednesday's loss. "It's been a lot of work, not only on my end, but [by] the trainers and the weight coach and everyone involved. They've put a lot of effort into me, and I couldn't thank them enough. I'm still feeling good late here in the season."
That was evident early on Wednesday, when Wacha's fastball velocity reached as high as 99.1 mph. It was the second-hardest pitch he had thrown all season.
"It's just him showing everyone that he's strong," Matheny said. "Unfortunately, the seventh might make a different argument, but not for me. He has answered the bell. He has continued to do the work that he needs to do to stay strong and take the ball, and he did a great job all the way through."
Wacha matched his career high with 30 starts and established a career high with 158 strikeouts, the final eight of which came on Wednesday. His ratio of 0.92 home runs allowed over nine innings led the Cardinals' staff.
And while there were continued troubles navigating through a lineup the second or third time through, there was also progress with the development of his two secondary pitches -- his cutter and curveball.
"I just tried to work about my business and how I felt internally and go out there and try to make every start I can and compete my tail off," Wacha said. "I feel fine. I feel good. Hopefully, this isn't my last start."