Matt Garza has always had the stuff to be an elite top tier starter, but never quite put it all together until last year. As Dave Allen and Josh Weinstock explained during this past season, a heavier reliance on his secondary pitches was instrumental in his turn around from three consecutive seasons with an FIP between 4.14 and 4.42 to a breakout 2.95 mark last season. I also looked at how his increase in secondary offerings led to a 4.25 K/BB rate against left-handed hitters specifically for RotoGraphs, a heavy improvement over his past marks against opposite handed batters.

Yesterday, Garza dominated a sturdy Brewer lineup as he finished one out away from a complete game shutout. While former Cy Young winner Zack Greinke was his opposition, Garza was the better pitcher yesterday — something that is not out of the realm of possibility of remaining true throughout this season.

Garza’s slider was absolutely dominant yesterday, and was the main reason for his extremely impressive outing. Six of Garza’s nine strikeouts came via the slider, with another coming with a curveball. Garza threw 31 sliders in 119 pitches, good for 26% of his overall pitches. 22 of the 31 sliders, or 71%, were thrown for strikes while 22.58% were swinging strikes. The pitch has become a legitimate out pitch for Garza, something he did not utilize nearly as effectively in Tampa Bay or Minnesota. It helps that the rest of his pitches were rather effective also, specifically his primary four-seam fastball. Even with other solid pitches, he recorded just eight swinging strikes with non-sliders compared to the seven he recorded with his slider. MLB.com’s highlights of his outing are embedded below.

Garza’s small home run issue also subsided last season. After recording back-to-back seasons with a home run per fly ball rate above 10% in a pitcher friendly ballpark, he recorded a 7.7% mark last season in hitter friendly Wrigley Field. His altered repertoire seems to have had an affect on the home run rate. From the data below, I can see two ways this helped his home run allowed rate. First off, he allowed fewer fly balls last season, which helped keep his overall home run allowed total down — he sat at 14 last year compared to 28 and 25 in the two seasons previous. You can see in this chart, taken from Brooks Baseball, that his fly ball per ball in play rate is lower almost across the board. Secondly, since his fastball is his most commonly thrown pitch and he records more fly balls with that pitch over his career compared to his other pitches, the lower reliance on the pitch has made it more difficult for hitters to wait on his fastball. Since a 95 mile per hour fastball is easier to square up than an 86 mile per hour slider, the increased reliance on secondary offerings has helped him lower his home run rate as well as his fly ball rate — a solid formula for success in combination with an improved strikeout rate.

The heavier reliance on secondary pitches has certainly benefited his strikeout rate, but according to pitch type linear weights, his fastball was more effective last year than it has ever been per pitch — both BIS and PITCHf/x agree in this respect. Again, forcing hitters to expect a fastball less frequently seems to have had an added benefit even outside of his slider becoming a top notch pitch.

For some reason, Garza was a fastball-heavy pitcher in Tampa Bay, and he was still an effective starter during his days with the Rays. Since moving to Chicago, he’s evolved into a more complete pitcher and is currently reaping the benefits. While it is just one performance, yesterday’s outing is just more evidence that that his breakout campaign last season was no fluke.