← BackZack Kelly
BOS · RHP · 2026
16.3 IP · 71 BF · 283 pitches · 2026 season
MED Descriptive — not a forecast
115
Stuff+
96th percentile
106
ABStuff+
92th percentile
110
Pitching+
92th percentile
19.7%
K%
42th percentile
9.9%
BB%
42th percentile
4.07
FIP
74th percentile
Grades describe this season's stuff and run prevention. They are not forecasts: on clean season pairs the model has not beaten naive persistence (RESULTS-MLB §13), so nothing here projects next season.
Percentile rankings
vs 2026 graded MLB pitchers · 16.3 IP · 71 BF · 283 pitches · 2026 season
Stuff
Stuff+115
96th percentile
ABStuff+106
92th percentile
Whiff%18.7%
25th percentile
CSW%30.7%
22th percentile
Results
Pitching+110
92th percentile
FIP4.07
74th percentile
RA/91.10
95th percentile
GB%46.9%
73th percentile
Command
K%19.7%
42th percentile
BB%9.9%
42th percentile
K-BB%9.9%
40th percentile
Velo90.1
54th percentile
How to read these
Each row is his rank, 1 to 99, among all graded MLB pitchers this season; the tick is the median. Green is good for him, red bad, whatever the stat's direction (a low FIP ranks high). Grey circles are descriptive rates with no good direction, and n= in place of a rank means too few events to rank. Grades are descriptive, not forecasts.
ArsenalKey columns; every column is on the Arsenal tab
Movement Profile
CH-2.8/-4.4SI+2.1/-1.1CT-0.8/+1.8SW+1.9/+4.7FF+0.1/+0.9ring = slot expectation ±1σ/2σ · HB mirrored for LHP · descriptive
Release Traits
Height: 5.39 ft (±0.13)
Side: -3.24 ft (±0.17)
Extension: 7.14 ft
Season means; the ± is the SD across his pitches. Per-pitch release plots land in a later wave.
Batted Ball Against
Pitch
N_BIP
GB%
FB%
LD%
PU%
Avg EV
Avg LA
HrdHit%
CT
22
31.8
22.7
45.5
0.0
86.3
12.7
54.5
SW
12
50.0
25.0
8.3
0.0
78.7
19.9
25.0
SI
11
54.5
9.1
36.4
0.0
82.0
2.4
27.3
FF
4
100.0
0.0
0.0
0.0
79.1
21.2
25.0
Every pitch type he threw, ordered by balls in play. Rows under 5 BIP are dimmed rather than dropped — a slider put in play twice is a fact about the slider.