Stephen Piscotty: All-around above-average hitter

Former first round draft pick and the Cardinals' back-up plan after missing out on Jason Heyward, Stephen Piscotty just keeps producing. After hitting to a 133 wRC+ and a .372 BABIP in 256 PA last year, some wondered if Piscotty would keep it going. He has and then some, posting a 143 wRC+ going into yesterday on a .370 BABIP. The projections have responded, with fangraphs' Steamer and Zips based depth charts increasing his projected wRC+ from 106 before the season began to 113 currently.

What caught my eye looking at his stats the other day is that Piscotty has succeeded this year by being above-average at all four main parts of hitting. He has performed better than average at limiting strike outs, drawing walks, hitting for extra base power, and getting hits on balls in play. A player's BB%, K%, ISO, and BABIP certainly aren't the only ways to evaluate a hitter, but it's the four stats I first go to in order to get an idea of how that player produces value at the plate.

I wondered how often it is that a hitter is able to be above-average at all four of these stats. Using Fangraphs' ability to download their leaderboards, and some programming skills, I compiled a list of qualified hitters who have so far been above average in all four categories in 2016. Here is said list:

Not every great hitter show up here. All-universe slugger Bryce Harper for instance is not included, though only due to a fluky low BABIP. Mike Trout isn't on here either. It is however, a rather large amount amount of good hitters. Basically, you have to be at least good if you're above-average in all four aspects, which certainly shouldn't be groundbreaking news to anyone. Matt Carpenter just barely missed the list, as he's currently sporting an exactly league average BABIP. If it regresses just one point towards his career BABIP, he'll be added on the list.

I wanted to get an idea of the floor of players that are above-average at all four aspects of hitting, so I looked to past seasons. I wanted to stay in our current run environment though, so I limited my search to qualified player-seasons from 2012 to 2015. That's a total pool of 570 qualified hitters, and it produced 50 player-seasons where the player was above-average in all four categories. Rather than post a chart of 50 players, I will link the google spreadsheet here for anyone interested enough to take a look. Each stat is converted into a "+" stat which is scaled to league average, so that a 113 means 13% above average, or in the case of K% where lower is better, an 84 means 16% below average. Unlike other "+" stats, this is not adjusted for park.

Miguel Cabrera is apparently the best at this exercise, with all four of his seasons making the cut along with his current performance in 2016. Andrew McCutchen and (surprisingly, to me at least) Prince Fielder made the list three times. Joey Votto, Josh Donaldson, Buster Posey, Jayson Werth, and Robinson Cano rounds out those who appeared multiple times. As for Cardinals, Matt Carpenter and Matt Holliday's 2013 season both make the list, but that's it. The lowest wRC+ on the list is Adam Lind's 2015 season, at 119. Of course, a hitter can be worse than that and still be above-average at everything, but the lowest mark out of 50 (64 including 2016) seems like a good bar for the floor of a hitter that is above-average at everything.

With it being so high, Piscotty's BABIP is bound to regress. But the projections still like him going forward to be above average at .319 for Fangraphs' depth charts. This article uses an xBABIP calculator and found his expected BABIP at .350 last year. So he'll most likely stay above-average there, despite some regression. He has some growth to be had in the ISO department though. Baseball Heat Maps currently has Piscotty at 13th highest fly ball distance out of 253, just outside the top 5%, and that's actually down a couple feet from where he was last year, when he placed 13th out of 284 in the stat. Despite that, his HR/FB rate sits around average.

As we've seen with Marp in the last year and a couple months, with increased power he could also increase his walk numbers, as pitchers would be more careful throwing strikes to him. There's another reason however to believe the walk rate could increase. Here's a split showing some plate discipline stats in April, as well as May and the first game of June:

In May, Piscotty cut nearly 6 points off his O-swing%, while adding on more than 5 points to his Z-swing%. He actually swung at nearly the same rate as he did in May, just with much better strike zone management. At the same time, he upped his Contact% nearly 4 points. Piscotty was seeing the ball way better in May than April, both in terms of making contact and discerning which pitches to swing at. Maybe April is normal for him and he just had a hot month in May, or maybe he just wasn't seeing the ball well in April and May was more normal going forward. Almost certainly the truth lies somewhere in the middle, and this will be something to watch going forward.

How big of a change is that O-Swing%? Enough to make the top 10 in terms of largest improvement from April to May:

This is the top 10 from a list of all hitters who had a qualified amount of PA in both April and May, a pool of 152 players, putting him in the top 3% in terms of decreasing swings at pitches outside of the zone. The Z-Swing% makes it all the more impressive though. Evan Longoria, for instance, led the league in decrease in O-Swing%, but also decreased his Z-Swing% almost the same amount. Longoria didn't have better strike zone management, he was just more patient in general. Kole Calhoun decreased his O-Swing% by almost as much as Stephen, but also lost rather than gained ground on swings in the zone.

You might think such a reduction in swings at pitches out of the zone would increase a player's walk rate. That's not what happened for Piscotty though, who actually reduced his walk rate from April to May. That was because of a confluence of three factors: (a) the increase in Z-Swing% noted above, (b) an increase in Contact%, and (c) an increase in the percentage of pitches thrown in the zone to Piscotty (or Zone%, shown in the first chart). Increases in pitches in the zone, swings in the zone, and overall level of contact all led to Piscotty's plate appearances lasting shorter than usual, resulting in slightly less walks. That's not a big deal though, as those three and a lowered chase rate had a much more profound affect on his strike out rate:

This is the Top 10 in decreased K%  from April to May, with the same 152 player pool, and as you can see, Stephen is virtually tied atop the leaderboard. May's 11% figure was less than half of April's 24%. Piscotty had the 33rd largest Z-Swing% gain and the 30th best gain in contact%, again from the same 152 player pool.

This is all to say that while it may just look like a few percentage points here and there, Piscotty actually did have drastically different performance from April to May in terms of plate discipline and contact. It'll be interesting to watch how things change going forward, and where on the spectrum he ends up falling between April and May's numbers.

I do expect the power that the underlying stats suggest will materialize, and with it, the walks will increase as well. And I agree with the projections that Piscotty has the skill to post a higher than average BABIP, if not as sky-high as his current number. The contact numbers also indicate that he should be able to post below average strike out rates. As the numbers presented here show, it's hard to be consistently above-average at all four stats, but he has been so far in 2016, as well as in his short MLB career, and their is reason to think he can do it going forward. This is all to say that I think the Cardinals have a great hitter on their hands in Stephen Piscotty.