Matt Garza followed Kyle Lohse‘s poor start on Opening Day with one of his own, managing just five innings and allowing four runs on eight hits. The Colorado Rockies hit Garza so hard, that he and Jonathan Lucroy switched up their signs midway through the game in case he was tipping his pitches.

So what went wrong?

Throughout spring training, Garza boasted that he rediscovered his slider. Here’s what he told MLB.com after his final spring training start:

“Losing that last year, it taught me how to pitch. When I didn’t have my slider — I was a fastball/slider guy — now I had to learn how to pitch. I have a curveball, I developed a changeup. Yeah, it was a terrible year without strikeouts, but I was able to get through it and make pitches and get out of stuff. I still don’t forget that, and now I have my slider. It’s like, ‘Yay, new toy!’ I feel confident with my stuff right now, and I want to keep it going.”

Despite his confidence, Garza only threw his slider nine times. That doesn’t sound like much of a new toy, nor does it sound like it’s very fun to play with (three of the four sliders that were put in play went for base hits). The truth is, however, that Garza needs his slider to be successful, and from his comments above, he’s well aware of that fact. He threw it 21.7% of the time in 2014, the lowest rate since 2010, and that needs to change this season. Increased slider usage should create an uptick in strikeouts (he had just two on Tuesday) and take pressure off his fourseam fastball of which he threw 43 times out of 81 pitches.

In addition to his limited slider use, Garza had a difficult time locating his pitches.

He spent a lot of time in the middle portion of the zone, which is where the majority of Colorado’s hits came from. Garza rarely challenged hitters up in the zone, and when he did, they fouled him off. Garza was actually pretty lucky he allowed just five runs considering the Rockies posted a .381 BABIP that included more doubles than I could count. Fortunately, he kept the ball in Miller Park and Garza allowed just one free pass.

Going forward, Garza needs to work the corners more. He also can’t be afraid of utilizing his slider more or going up in the strike zone with his 93 mph fastball.

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