Bullpen Pitch Arsenal Scores

Last week, I took a look at the Mariners' starting rotation using Pitch Arsenal Scores. Based on individual pitch types, we're able to see which pitchers have the best pitches to call on to get batters out. It has its limitations -- it doesn't account for called strike rate, Zone%, or ability to induce weak contact -- but it's valuable in that it shows us which pitchers are reliably able to force batters to swing and miss or pound the ball into the ground.

For the relievers, I adjusted the league averages to account for the different sample. Relievers are able to generate much higher whiff rates as they regularly enjoy the platoon advantage and are throwing at near maximum effort. I also adjusted the weights I assigned to whiff rate and groundball rates based on their correlation with the sample's ERA, SIERA, and xFIP.

I also have to note that sample size becomes more of a problem with relievers. I still maintained the 100-pitch minimum when assigning a score to specific pitches. The graphs will still show pitches under that limit to give you an idea of where they might score but for the actual calculation of the Pitch Arsenal Score, I left them out.

On to the data!

Fernando Rodney

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	96.43	11.9%	21.2%	1.80	0.16
Sinker	95.52	56.2%	16.1%	4.62	0.12
Change	83.14	31.9%	45.8%	1.42	0.52
					0.80

Our venerable closer checks in with an arsenal almost a standard deviation above average. He's able to generate an above average whiff rate with all of his pitches, though none of them are outstanding. Still, the sum of three above average pitches makes for a deadly arsenal.

Danny Farquhar

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	94.42	13.1%	31.9%	0.67	1.02
Sinker	93.79	7.6%	25.7%	1.43
Cutter	90.19	56.5%	18.2%	2.43	-0.45
Curveball	76.56	15.8%	40.7%	1.14	0.07
Change	85.41	7.0%	52.9%	4.00
					0.64

Danny Farquhar's Arsenal Score suffers from the sample size demons. Both his sinker and his changeup rate excellently, but since he doesn't throw them that often, they aren't calculated into his overall Pitch Arsenal Score. It's also interesting to note that Farquhar's cutter -- the pitch that advanced his reinvention -- scores the lowest by this metric. He doesn't really use it as an out pitch so the fact that it doesn't generate many whiffs is okay.

Tom Wilhelmsen

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	96.06	43.2%	24.7%	1.94	0.53
Sinker	96.68	14.9%	23.2%	6.50	1.12
Cutter	91.68	6.8%	29.7%	2.00
Slider	87.88	11.6%	30.4%	1.67	-0.52
Curveball	78.92	14.9%	37.5%	5.67	0.19
Change	88.75	8.5%	44.4%	4.80
					1.32

Wilhelmsen started throwing his slider in earnest this last year and it hasn't done him any favors. All five of his other pitches grade out very well. Although he's known for his big sweeping curveball, it's definitely not his best pitch by this metric. It looks like this is another case where the limitations of Pitch Arsenal rear their head. Wilhelmsen has generally been able to run fairly high called strike rates with his curve as he uses it mainly to freeze batters who are thinking about his mid-90's fastballs.

Yoervis Medina

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	95.73	19.6%	14.8%	2.71	-0.32
Sinker	95.57	47.8%	17.8%	3.47	0.24
Curveball	86.01	31.9%	47.5%	2.17	0.53
					0.45

When I think about Yoervis Medina's curveball, I think about this pitch.

Sure, that's a called strike and he misses his location completely, but that's just nasty. He's also able to generate his fair share of whiffs with his curve too, making it the best pitch in his arsenal.

Charlie Furbush

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	92.82	47.3%	22.0%	1.38	0.16
Sinker	91.83	9.1%	25.9%	1.00
Slider	81.84	37.8%	42.1%	1.86	0.19
Curveball	78.89	5.6%	25.0%	0.50
					0.35

Charlie Furbush's curveball and sinker are vastly different. He's able generate a huge amount of whiffs with one and very few with the other. He doesn't throw either of them very often so they don't skew his Arsenal Score, but if he did throw them more, I'd like to think that they'd just cancel each other out.

Dominic Leone

Pitch	Velocity	Frequency	Whiff/Swing	GB/FB	Pitch Score
Fastball	95.42	49.7%	20.8%	2.73	0.28
Sinker	94.94	6.0%	25.0%	0.00
Cutter	90.78	21.4%	33.0%	3.67	1.12
Slider	84.09	18.4%	46.5%	5.25	0.89
Change	88.19	4.4%	33.3%	4.00
					2.29

This was the biggest surprise for me. Dominic Leone was able to generate a huge amount of whiffs with three of his pitches. On top of that, his batted ball profile trended towards grounders more than fly balls (except for his sinker, oddly enough). His cutter and slider are deadly weapons and are the main reasons why righties had just a .229 wOBA against him last year.