On Tuesday, in his 99th career start, Michael Wacha threw his first career complete game shutout. Due to a pitch count nearing 100 through eight, some questioned leaving the injury-plagued 26-year-old in to finish out the ballgame. I was not one of them. Complete game shutouts (CGSOs) are a big deal for a pitcher. For hitters, some comparable accomplishments include a cycle or a three-homer game. Thus, when a reasonable opportunity for a CGSO presents itself, jump on it, while obviously still remaining cognizant of the pitcher’s overall health. After 11 days of rest, will 119 pitches affect Wacha’s next start? Maybe so! But honestly, the fact that the start comes against the surging Chicago Cubs is probably more of a contributing factor.

Just yesterday, site owner Brenden Schaeffer set the table for this post by attempting to make heads or tails of Wacha’s recent success. His conclusion, word-for-word, “I have no freaking clue.” Wacha’s “recent success” equates to a sparkling 1.01 ERA over four starts. Further, Wacha has twirled a WHIP less than one (0.863), has surrendered zero home runs, and has recorded more strikeouts than innings pitched:

Always considering the small sample size argument, what has been different for Wacha over his last four starts? The first place to start is pitch usage rates. Has his repertoire evolved at all? Has he become more comfortable throwing one pitch over another? Or, has everything stayed seemingly the same?

Michael Wacha pitch usage rates

It is clear that Wacha has completely disregarded my offseason recommendation by throwing even more cutters over his last four starts than he did over his first 13. And it’s working as the pitch has struck out eight hitters and has allowed only two mere singles in the given time frame. The sinker, though it made a noteworthy introduction into his repertoire during his first two starts, has been scrapped entirely. He is going to his fourseamer slightly less frequently than before, but by rate, it still ends up being thrown virtually every other pitch. Frankly, a pitch thrown this frequently deserves some analysis. Let’s take a closer look at what I consider more important than the pitch’s velocity (which has held steady, by the way): location.

Locating the fourseamer

Versus lefties

Versus righties

What can be learned from the heat maps embedded above? If you focus on the cores (dark spots), it’s simple, really. First, as we should all know by now, Wacha has long struggled with fastball command. I have written about it. Fellow blogger Steven McNeil has written about it. Heck, even the Fox Sports Midwest broadcast crew mentions it during his starts.

Well, what we have seen over the last four starts (in clear contrast to his first 13) is a clear vision and successful execution by a pitcher. He is locating the fourseamer down and in to righties and up and away to lefties. What’s important is that both locations sequence and tunnel perfectly with his changeup, cutter, and even curveball, for that matter. When looking at a smaller sample size, heat maps tend to look more diffuse — with more than one “core location” popping up. As you can see, this has not been the case for Wacha — representing a marked improvement in fastball command.

All four pitches appear to be working

Strikeout of Michael Conforto (BrooksBaseball At Bat)

While the curveball is the least-discussed Wacha pitch, when he masters its release point, it can be downright filthy. It certainly helps being 6’6″. In the slow-mo feed below, you will see that when the pitch crossed the plate, it was just barely below the strike zone. Hence the swing from the red hot Conforto (2017 wRC+ 149) despite the pitch ultimately landing in the dirt.

Strikeout of Yoenis Cespedes (BrooksBaseball At Bat)

I admit to being one of the biggest critics of Wacha’s cutter. Yet, if it is inducing swings out of the zone, as it did on Tuesday night, I have zero complaints about it. I only worry when he gets under it on his release point and it floats up in the zone. Either way, this 92.2 MPH cutter — immediately following a 77.4 MPH curveball — to strike out Cespedes was dirty — just look at how much Yadier Molina moved his glove to catch it.

Strikeout of Lucas Duda (BrooksBaseball At Bat)

You know you’ve thrown a good changeup when you’re able to induce two swings and misses in a row. Wacha did just that to Duda with an 89.5 MPH changeup on the outside corner. The changeup may not be as effective as it once was, but if this newfound fastball command is real, look for the pitch to return to 2013 form. Because no matter how filthy a changeup can be, the ceiling of its effectiveness is ultimately limited by the fastball.

Strikeout of Jay Bruce (BrooksBaseball At Bat)

I will admit to saving the best for last because well, Wacha, himself, saved his best for last. To nail down the CGSO, Wacha painted a 99.1 (!) MPH fourseamer past Bruce for strike three. It could have been a called strike even if Bruce didn’t swing at it. I say “could have” because while being on the corner, it was up in the zone, and umpires sometimes struggle to call the high strike. If you haven’t noticed it already, please focus on @cardinalsgifs‘ freezing effect of Molina’s glove. The target was set and Wacha sniped it. Perfectly.

Just a little bit (for now) about pitch sequencing

Similar to what he did for my post on Carlos Martinez, I asked the great Zach Gifford to collect aggregate two-pitch sequence data on Wacha swings, whiffs, and called strikes. Please note, Zach’s data will eventually be used for a full post. In the meantime, I have a few nuggets to share. Remember, here is how we divided up the hitting zones:


Regardless of batter handedness, Wacha loves going up and away (zone 1) with his fourseamer, and he isn’t afraid to go to it back-to-back. Overall, a fourseamer-fourseamer, 1-1 combination leads to pitcher-controlled strikes — either whiffs or called — 23.75% of the time. And remember, zone 1 contains the core location of Wacha’s fourseamer to lefties over his last four starts, providing part of the foundation to his success. Regarding Wacha’s core location to righties over his last four starts — or zone three shown above — the 6’6″ righty garners a lot of called strikes from this location, particularly utilizing the fourseamer. In fact, he’s sequenced this location 149 times, receiving 34 called strikes — for a rate of 22.82%. This is particularly high rate for a straight pitch like the fourseamer.

So, is good Michael Wacha back? Honestly, it is still too soon to tell, but continued command of the fourseamer will certainly go a long way. Given Mike Leake‘s recent struggles, Wacha is that much more important for the St. Louis Cardinals down the stretch. If they want to leapfrog the Cubs, Brewers, and Pirates, Wacha’s performance will be of supreme importance. Finally, for those that are down about yet another bad Cardinals’ loss, I leave you with the following GIF:

As always, credit to @cardinalsgifs for the GIFs used in this post. Follow him on Twitter.