Dillon Maples is not yet a great major league pitcher. On April 28th, he walked the bases loaded, forcing manager Joe Maddon to bring in Tyler Chatwood, who was apparently deemed more likely to throw strikes.

Like Chatwood, Maples is a Cubs pitcher with a high-spin repertoire and command issues. He consistently ranks near the top of the majors in both spin rate and walk rate. Watching this archetype of pitcher is a frustrating experience for fans, but for hitters it can be downright disconcerting.

When Maples is off, it often resembles this:

When he’s on, though, it can look like this:

Hitters have good reason to fear Maples, considering his frequent lack of command and his high velocity. Here are two at-bats from a game against the Brewers from last year.

These two pitches have the highest spin rates of any pitches that Maples has thrown, and one of them hit Aguilar in a dangerous area:

But the high-octane fastball and lack of command aren’t the only reason Maples scares hitters. The more entertaining and less dangerous reason is the incredible movement on his slider. Right-handed hitters in particular seem unable to pick it up out of his hand. This often causes a flinch-and-turn motion even when the pitch is a strike, sometimes even in the middle of the zone. These three at-bats nicely exhibit the effect Maples' slider has on hitters:

I’ve saved the best for last, though. On Wednesday’s game against the Mariners, Maples was asked to get the last three outs of a blowout win. He struck out the side, ending with this sequence to renowned slugger Edwin Encarnación:

Encarnación looks uncomfortable throughout the entire at-bat, and doesn’t come particularly close to taking a threatening pass at any pitch. As it has always been with Maples, the stuff is there. We get to watch him take hitters out of their comfort zones, even if he isn’t able to become a shutdown reliever.