Day after day, amateur baseball writers like myself and professional writers seem to think they are smart by bashing on the beloved righty Jared Weaver of the San Diego Padres. Granted, Jared Weaver has been utterly atrocious by every baseball metric available and every radar held pointlessly towards his “fastball”. Seemingly unnoticed, however, has been the work of another atrocious righty playing for a team under renovation. Bronson “Don’t Call It a Comeback” Arroyo continues to quietly die in a Reds uniform and for the past 13 starts it would seem that nothing positive has come from his return to Cincy. That line of thinking would lead most down the path of completely ignoring his work, but I find that we can use Bronson as a sort of teachers example. Let’s look at the former steady starter in order to understand the importance of Pitching Peripherals in judging today’s variety of starters.
I have chosen three percentage based statistics to use as a baseline: GB%, HR/FB, and Pull%. In case you are unaware as to what those exactly mean.
GB% = the percentage of batted balls hit on the ground
HR/FB% = ratio of home runs out of fly balls
Pull% = the percentage of batted balls that were pulled by the hitter
It appears as if Arroyo has relied on a ground-ball based arsenal for the majority of his career, yet his Fastball, Cutter, Sinker, Slider base has been extremely ineffective in that realm; producing GB rates that are neither consistent or near the league average.
Looking at the GB% of each of his major pitches in 2017 we can see where some of the faults lie.
Fastball = 49.3%
Cutter = 21.2%
Sinker = 40.7%
Slider = 19.0%
His fastball is the only pitch resulting in above average results but Arroyo has been throwing it less and less as his velocity declines (more on that later).
Relative to an above-average Starting Pitcher in Carlos Martinez (50.9 GB% 67 ERA-) and an almost exactly league average Starting Pitcher in Daniel Norris (40.7 GB% 101 ERA-); it is clear how below average Arroyo has been in generating ground balls. Obviously the argument could be made that Arroyo is therefore a Fly Ball Pitcher but that is where our next statistic comes into play.
In order for Arroyo to be successful while not producing a league average GB%, then he must be able to limit the amount of fly balls that head into the stands. As you probably guessed, Arroyo has been unable to accomplish this feat.
Homeruns may be up overall in the Majors but they are drastically up for Bronson. As we did with GB%, lets compare this statistic with two other Major league Starters: Danny Duffy (5.1 HR/FB%, 80 ERA-) and Tanner Roark (12.3 HR/FB%, 100 ERA-).
So if the balls hit in the air are going for dongs… the question becomes why?
The hits are certainly not clearing the fence by luck.
I believe it is correct to say that the league is crushing his middling 84mph fastball, but some of the blame for can be placed on Arroyo’s fastball location.
Arroyo is leaving meatballs right over the dish for the rest of the National League to crush. Let’s again see how Arroyo’s Pull% compares to other Pitchers: Stephen Strasburg (35.1 Pull %, 75 ERA-) and Alex Cobb (43.2 Pull%, 99 ERA-).
To quote Mr.Arroyo after his most recent shelling. “You have to put up enough quality starts for a ball club to want to keep you around, you know? That could have been the last time I was on the field, yeah. It’s just the way it is.”
Even Bronson knows that things aren’t boding well for him going forward, even on a suffering Reds team, but just because it’s over for him doesn’t mean we can’t use Arroyo as an example. These Batted Ball Percentages allow us to see how certain statistics effect Pitchers who are below average, average, and above average.