Matt Wisler needs something to go along with his slider in 2017

Matt Wisler was a pretty bad pitcher last season, and that’s disconcerting for a few reasons.

One reason, obviously, is that the Braves — like every other Major League team — would like to see improvement every year with their younger players. Another is that Atlanta was banking on Mike Foltynewicz and Wisler to carry a significant portion of the rotation load in 2016, along with Julio Teheran. A third (and perhaps the most important) reason, is that I bet Brad Rowland that Wisler would have a sub-3.20 ERA on a pre-season Talking Chop Podcast.

Thanks Matt. You made me look like an idiot.

You did not wind up with a sub-3.20 ERA, and among MLB starters with at least 150 innings thrown, only Jered Weaver (-0.2) and James Shields (-0.2) had a worse fWAR than you (0.4).

The good news is that I haven’t given up on you yet.

Partially because the two Wisler starts that I was able to watch this year in full were two of his top-3 outings of the season — on August 25 vs. the Diamondbacks (75 GameScore) and his next start on August 31 vs. the Padres (67 GameScore). Another reason I still have some faith in Wisler figuring things out is because when he struck out a career-high 10 batters in that game vs. the Padres, he flashed a pretty good pitch: the slider.

I tweeted that after Wisler’s game-high performance vs. San Diego, which was one of the most encouraging outings of the season for him — even if the Padres had the second-worst offense in baseball and the second-highest K% as a team.

That one start highlights the improvement that Wisler saw from 2015 to 2016 with the pitch.

So a slight bump in wRC+ vs. the pitch and pretty significant steps forward in all the other categories. He struck out more batters on the pitch, he got more swings and misses, he got more chases outside of the zone and batters made significantly less contact in general.

All good signs.

To top it off, Wisler also increased the usage of his slider from 2015 to 2016, which inherently seems like a good idea. If you have a really good pitch, use it more often. And that’s what he did:

So, if his slider took steps forward in 2016 and he increased the usage of it, why was he still such a bad pitcher? The answer appears to be pretty simple: all of his other pitches were not good (ie: bad).

Per Fangraphs.com PITCHf/x data, all of Wisler’s other pitches (four-seam, two-seam, curve and change) allowed wRC+ numbers significantly higher than the league-average of 100. In fact, during the first two seasons of his Major League career, Wisler’s slider is the only pitch that’s resulted in wRC+ numbers less than 100:

The simple solution when looking at all of this might just be to have Matt Wisler throw his slider even more during 2017, but that’s ignoring a key fact of being a successful Major League starter: you can’t survive with just one pitch.

You can’t even be a good starter with two pitches, unless they’re both just plus-plus all the time. Big league hitters are too good, and they’ll make the adjustment. Which is what they managed to do against Wisler this season.

If you take a look at the pitch usage numbers in the second table, you’ll notice that Wisler either threw a fastball or a slider 89 percent of the time. He used both his changeup and his curveball just about 10 percent of the time.

Essentially, opposing hitters could stroll to the plate only having to worry about a fastball and slider. Given that Wisler throws an exceedingly average fastball (which peaked at 95.7-mph in 2016), that’s not much of a challenge for Major League hitters. And when hitters did manage to successfully wait for the slider and barrel it, they did more damage.

Wisler’s HR/FB rate went from a pretty solid 10.5 percent in 2015 to a slightly worse than league-average 13.7 percent in 2016. Many of those home runs came against the slider, and at a significantly higher percentage than his rookie season.

In 2015, Wisler gave up 16 homers; 15 came against a fastball (93.75%), while just one came against his slider (6.25%).

In 2016, Wisler allowed 26 homers; 15 against the fastball (57.69%), 8 against the slider (30.77%), 2 against the changeup (7.69%) and one against the curve (3.85%).

Hitters also nearly double their isolated power vs. the slider from 2015 to 2016, going from 0.079 to 0.148.

Those numbers didn’t happen because something with the pitch changed from year to year. The velocity and movement of the pitch during his first two seasons are almost the same, even while throwing 272 more of them during 2016 than 2015.

The slider was a good pitch last season, but again: you’re not going to get by as a Major League starter with just one pitch. Both his curveball and changeup (the pitch he worked on all offseason) took steps backwards during 2016 according to the numbers, and barring a sudden jump in fastball velocity or a huge step forward in command that’s going to prevent him from being successful.

Ideally, Wisler would be able to figure out the changeup, as that pitch would allow him to more easily attack left-handers, who managed a .334 wOBA against him in 2016 (righties had a .313 wOBA). Unfortunately, that was his worst pitch according to the wRC+ numbers. Even if it’s not a change, a third pitch is necessary to keep hitters off-balance and prevent them from sitting on the fastball or slider.

Obviously I think highly of the slider, and the numbers bare that out. I think his fastball can play in the bigs as well, but if those are the only two pitches he’s throwing he’s going to keep having these struggles. Again, I still have faith that Wisler can figure things out, and hopefully in 2017 he can find that third pitch.

Either way though, I’m not betting that he posts a sub-3.20 ERA again until I see some sort of development in the repertoire.