Since early May, Justin Verlander’s rebuilt cutter-style slider has been his best weapon on the mound. This lethal development in Verlander’s repertoire is helping him to his best strikeout rate in a half decade. As the Detroit Tigers’ resurgent ace has grown more comfortable with his command, the pitch has become a veritable Swiss Army knife in his toolkit.
According to FanGraphs' pitch values, Verlander’s slider ranks 11th among all MLB starters in pitch value per Fangraphs. Going back through the past six seasons, Verlander’s slider previously had its highest value in 2012 when it ranked 14th. The comparisons between those two peaks are pretty striking. Hitters in 2012 posted a .245 wOBA against Verlander’s slider. This season, they have managed a truly miserable .217 wOBA against it. Verlander threw 466 sliders in 2012, and is currently well beyond that mark already in 2016. While he actually had a much higher swinging strike rate in 2012 (20.8 percent as compared to this season’s 14.5 percent mark), he is getting the best results of his career overall.
There has been plenty of confusion as to whether the pitch is a slider or a cutter. Since Verlander himself denies throwing a cutter, we’ll just run with that. He is using the revamped version more often, and in a wider variety of ways than the traditional version he had most of his career. Let's look at the many ways in which Verlander is using the pitch, and how it plays in the velocity band between his fastball and curve.
Typically, a righthander’s slider is best used biting down and away from a right-handed hitter. Many pitchers are wary of throwing it to a hitter of the opposite hand. The slider is a pitch that will be thrown for a strike at times, but it’s also largely designed to bait hitters into swinging at a ball or a borderline strike at the bottom of the zone.
Verlander does this as well, but he’s also going way beyond that, into territory typically reserved for a cutter. And it's the rest of his arsenal that helps him do it.
What's notable here are the varying ways in which Verlander uses the pitch against left-handers. We see Alejandro de Aza going down swinging on a gorgeous back-foot slider down and in. Verlander sets him up for it by going away with the fastball twice earlier in the confrontation. With de Aza conscious of the fastball tailing out of the zone away, the slider looks like a fastball coming middle in right through de Aza's sweet spot, before it disappears.
In the second clip, Verlander already has Curtis Granderson guarding against getting blown away by one of the best elevated four-seam fastballs in the game. With that pitch previously established, Verlander starts the slider at the same eye level as the high fastball and drops it just above the strike zone. The pitch is above the inner third of the plate as well. Not only is the deception caused by the high fastball in play, but even were Granderson to react and get the bat on it, it's an extremely difficult pitch to barrel up.
Out of Verlander's hand, that could be a fastball, a slider, or a hanging curve. There's a range of some 16 miles per hour between the curve and his best fastball. Because the fastball has already been established, there just isn't time for a hitter to do much beyond guessing at a pitch that would be tough to square up even if it were expected. The quality of his pitches, and the fact that all of them are typically released toward the upper edges of the zone, makes each pitch even better by deceiving the eye. Few in the game are using the upper reaches of the zone the way Verlander is.
Here, we first see an example of Verlander attacking inside under the hands with the fastball. This is a hallmark of Verlander at his best, and he'll do this to hitters of either hand. Tigers pitching coach Rich Dubee is a big proponent of establishing the fastball inside, but Verlander at his best has always done this. Visualize seeing that pitch, and then getting the slider de Aza saw -- or, more precisely, didn't see. Again, the two pitches complement each other beautifully, even in separate at-bats, as everyone watching sees Verlander pounding hitters inside and above the zone with precision.
The final piece is just an evil front-door slider that starts at Matt Reynolds' hands, and cuts back just enough to catch the zone. Verlander is known for pumping a mid-90s fastball right through that spot, and it induces a ton of whiffs and pop-ups. Here, he changes that up and turns the slider right into the upper right-hand corner of the zone. That's a pitch that few would throw, but Verlander's use of the top of the zone, and the inner edge with his fastball makes it extremely difficult to anticipate a breaking ball there. Even if Reynolds saw breaking ball out of Verlander's hand, that could just as easily be a much slower 12-to-6 hammer on the inner edge of the plate.
Of course there's always the more standard version breaking away from a righthander. Mookie Betts put up a seven-pitch battle during Verlander's last start, but this one was too much.
Even when hitters connect against the slider, they're making extremely weak contact. Verlander has allowed an ISO of just .107 off his slider.
Now, watch Verlander's highlights from his fine outing against the Mariners, and you'll see the whole package at work once again.
The versatility on display in just these few examples should give hitters nightmares. There are plenty of other pitchers capable of using their slider inside to opposite handed hitters, but few of them have the rest of Verlander's repertoire and experience to work with.
Whatever the classification, Verlander is using the pitch like a cutter up in the zone (with an extra tick or two of velocity), like a conventional breaking ball style slider down, and with a willingness to throw it to any point around the edges of the zone or within it. Paired with a fastball that is again one of the most explosive in the game, and the willingness to throw it aggressively inside, Verlander has hitters uncomfortable and defensive. This is opening up all parts of the zone for the slider and for his curveball and changeup as well.
The evolution in stuff and approach speaks to Verlander's ability to improve, adapt, and dominate. It also points the way forward as he eventually does start to lose velocity again. Plenty of pitchers are having success with high backspin fastballs without the requirement of velocity. Verlander spins the fastball better than anyone in the game. Now he's got a slider that he can use effectively in a multitude of ways, to go with a good changeup and curveball.
Over time, there have been suggestions that Verlander needed to develop a two-seam fastball and become more of a ground ball pitcher to sustain a long tail to his stellar career. Instead, he has gone the opposite way to spectacular success all around the upper reaches of the strike zone. As a result, the Tigers may have their ace in form far longer than anyone expected.