STATE COLLEGE, Pa. -- In last night's loss to the Mets, Pirates pitchers gave up four home runs. It amounted to another day at the office for the group, who seemingly carry a predisposition towards the long ball that has put them squarely behind the eight ball far too often.
Or do they?
In fact, the four dingers that left Pirates pitchers' hands last night prompted me to dig into the numbers to pull out some common threads, to make sense of their perceived inability to keep the ball in the yard. What I found might help to put what seems like a huge deficiency in some much needed perspective. To do this, we'll look at the raw numbers and the context.
THE RAW NUMBERS
First, Pirates pitchers -- both starters and relievers -- had given up 148 home runs going into the opening of the Mets series, and that figure is good for 10th most in baseball. If we chop that up between the rotation and the bullpen, we see the starters giving up 86 home runs, tied with two other teams for the 12th most among starting units. The resulting 62 round-trippers allowed by the team's bullpen ranks as the eighth most in baseball.
Collectively, opposing hitters carry an average exit velocity of 103.2 MPH. That's good for seventh-lowest in baseball.
If we break out the types of pitches that are being punished, we'll see that 92 long-balls came off of fastballs -- that's good for seventh most in the league -- and Pirates pitchers averaged 93.0 mph of velocity on those pitches. That's good for seventh-highest as well. 39 of the 148 have come from breaking pitchers (11th highest total) while 14 have come from offspeed stuff (10th fewest).
The collective group of Pirates hurlers have allowed 54 home runs when behind in the count, 35 when ahead and 59 at even counts. The ranks for those peripherals are fifth highest, seventh highest and 11th highest respectively.
If launch angle is your thing, you're in luck: Pirates pitchers gave up an average launch angle of 28.4 degrees on their home runs allowed. This lands as the sixth-highest rate in baseball.
THE CONTEXT
Ok. If you haven't passed out from the sheer ugliness seen above, let's put some of this into context.
The batted ball data behind the homers tells an interesting tale. Pirates pitchers give up the sixth-highest fly ball rate at 37.3 percent, but the club's HR/FB (that's home runs per fly balls) clip of 15.0 percent puts them at just the 18th-highest clip.
This dovetails nicely with my next bit of nuance. These PBC chuckers seem to give up their fair share of cheapies. All told, 34 of the club's 148 home runs allowed going into tonight have seen exit velocities between 90 and 100 MPH, good for the fourth most in baseball. Are they line drives? Wind, or ballpark aided? Well, in a word, yes. But also, no. In another word, maybe? Of those 34, only one was a line drive. It will be near impossible to determine how much wind might have aided some of these, but we can say that if we neutralize park factors on this subset to league averages, there would still be 30 home runs seen, good for fifth-highest on this new, naturalized list. Perhaps the most damning bit of evidence towards a portion of these being lazier home runs than others comes from the fact that only eight of those 34 were classically "barreled" per Statcast.
Does any of this mean anything? Absolutely not, a dinger is a dinger, and the damage is done no matter how it happened.
But let's dig deeper, next looking at the counts in which these offenses occur. Getting behind is obviously never desirable for any pitcher, yet this group of pitchers seems to get victimized in obvious fastball counts. 40 of those 54 allowed when behind have come off of the fastball. This should come as no surprise as pitchers such as Chris Archer and others have trouble getting back into counts. On all pitches when behind in the count, the Pirates rank just 24th in all of baseball in strikes thrown while not put in play. Getting into better counts is clearly more important to this club than others. Or, at the very least, pitchers with great moving stuff like Archer, Joe Musgrove or Kyle Crick might want to lean into their breaking stuff a bit more when behind. Go with your best pitch in the most critical spots.
Launch angle is immaterial to the discussion here with such a tight range from the worst clubs to the best. As we've said before, launch angle on its own merit does not necessarily a dinger make. Exit velocity plays a part, too. As we said above, Pirates pitchers seem to be right in lock-step with the middle of the road, both in contact quality and launch angle, but one does not work without the other.
Just one last nugget for you that I found to be interesting: Archer's 24 home runs allowed account for 27.9 percent of his team's total home runs given up by starting pitching. Should that figure hold for an entire season, it would represent the third-highest percentage of home runs against a rotation given up by one member of the unit.
Though it may be frustrating to see the amount of home runs given up by the Pirates pitching staff, the long-ball is far from the one metric that can explain away an entire season's worth of up and down play. If you do find that one thing, though, please let me know.
