Wacha rejoined the Cardinals on Friday and a corresponding roster move is expected to take place Saturday before his fourth Major League start. The Cardinals adjusted the rotation, inserting Wacha in the second game against the Cubs to give the rest of the starters an extra day of rest. Adam Wainwright's next start, which was initially scheduled for Saturday, will be bumped to Tuesday, giving him an additional three days of rest and lining him up to pitch the series opener against first-place Pittsburgh.
In three starts with St. Louis, Wacha was 1-0 with a 4.58 ERA. He debuted with an impressive two-hit, one-run performance, but stumbled in his second start with six earned runs and 10 hits in just 4 2/3 innings. Wacha had a better outing in his last start -- two earned runs, five hits, three walks in six innings -- before he was optioned back to Triple-A when Jake Westbrook came off the disabled list.
"I think it was very valuable," Wacha said of his first big league stint. "It gave me an opportunity to come up here and see how my stuff played. It also pointed out a lot of my weaknesses, as well. Going back down to Memphis, I was able to work on those."
Wacha said one of those improvements was to work on keeping his pitches down in the zone. He said when he got into trouble in the Majors, it was often because of leaving pitches up over the plate.
The Cardinals have taken a cautious approach with Wacha, who has fast-tracked through the Minor Leagues since he was selected No. 19 overall in the 2012 First-Year Player Draft. The right-hander was on a six-day rotation schedule at Triple-A to monitor his innings load. Wacha posted a 3.51 ERA in six starts since his demotion, striking out 39 to four walks in 33 1/3 innings.
Wacha said he hasn't been informed of the team's plans for him beyond Saturday's start.
"The main focus is just going out there and pitching the best I can on Saturday," he said, "and hopefully help this rotation out, get a little breather, maybe a little rest in some of the guys arms and hopefully make a little run down the stretch here."
Chad Thornburg is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.