Mithrandir Metrics
Player Athletics Refreshed Sep 26 06:00 AM ET
Player profile / Athletics

Jack Perkins

P · Bats/Throws R/R · 6' 1", 220 lb · Age 26

Cards
15
Modules
1
Live Δ
yes
Club Athletics Position P Roster Current MLB team Status Healthy / active roster
Traditional line

Season by season

3D Pitch Lab Projections
WLERAGGSSVIPSOWHIP
2025324.19124338.2371.16
20263125.9036163116.01311.45
2 Seasons6145.4748206154.21681.38
At a glance

Season percentile report

The headline weighs outcome stats (xwOBA, barrels); each bar averages its full strip group below. 100 = best in MLB.

2026-09-26
42
Pitching
percentile
Pitching9 metrics
50
Arsenal6 metrics
70
Rolling projection

Preseason / current pace / Bayesian update

Rolling bands shrink current-season signal toward the preseason prior until the sample earns more weight.

2026-09-26
ERA preseason4.31
ERA current pace6.14
ERA rolling p505.57
Observed weight69%
ERA
4.44 4.98 5.57 6.17 6.70
FIP
3.62 3.98 4.39 4.79 5.15
K%
21.9% 23.1% 24.3% 25.6% 26.7%
BB%
7.9% 8.6% 9.3% 10.1% 10.8%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-09-26
Pitching · percentile strip
WHIP1.45
29
ERA6.14
9
BB%9.3%
45
K%25.0%
71 +25 vs proj
xwOBA allowed0.309
54 +23 vs proj
Barrel allowed8.3%
37
Fastball velo95.7
70
Hard-hit allowed36.9%
62
Whiff%25.1%
68 -23 vs proj
Mithrandir+

Stuff+ and arsenal context

How nasty this pitcher's stuff grades in our pitch-level model. Missing coverage is shown explicitly.

2026-09-26
Fastball Stuff+102
46
Mithrandir Stuff+105
75
Slider Stuff+108
93
Changeup Stuff+105
72
Cutter Stuff+103
70
Sinker Stuff+104
63
Rolling form chart

xwOBA allowed snapshot line

Live snapshot series; true 50/100 PA windows require PA-level logs

12 snapshots
Mithrandir Metrics ROLLING XWOBA LINE Parameterized Mithrandir chart rendered as SVG for templates and exports. season=2026 Rolling xwOBA allowed Perkins, Jack · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.313 0.309 2026-09-12: 0.3112026-09-13: 0.3112026-09-14: 0.3112026-09-18: 0.3112026-09-19: 0.3112026-09-20: 0.3112026-09-21: 0.3092026-09-22: 0.3092026-09-23: 0.3092026-09-24: 0.3092026-09-25: 0.3092026-09-26: 0.309 2026-09-12 2026-09-26 xwOBA allowed MITHRANDIR · CHARTS
Optimization map

Arsenal optimization map

Pitch-shape context from this pitcher’s current arsenal snapshot. Hover a pitch to inspect usage, movement, and bat-missing context.

6Pitches 2026Season 31%Top usage
ride armside gloveside +Arsenal gap +Shape contrast
Zone profile

Aggregate zone heatmap

Aggregate zone metrics from seasonal Statcast leaderboards.

Mithrandir Metrics ZONE HEATMAP Parameterized Mithrandir chart rendered as SVG for templates and exports. season=2026 Pitch Zone Profile Perkins, Jack · Aggregate zone metrics; not pitch-by-pitch locations Edge: 36%36%Zone: 46%46%Whiff: 25%25%Called strike: 16%16%First pitch strike: 49%49%Hard hit allowed: 37%37% Dashed border = aggregate mixed-batter zone proxy MITHRANDIR · CHARTS
Pitch arsenal

Usage mix, movement map, and Stuff+ composition

2026 pitch-level arsenal aggregates; current season takes over after 100 tracked pitches across at least 2 pitch types. Descriptive pitch-type Stuff+ composition. Not a promoted predictive metric.

Watch the pitches in 3D →

2026
Mithrandir Metrics PITCH ARSENAL DONUT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Perkins, Jack · 2026 arsenal snapshot 4-Seam Fastball: 30.6%Sweeper: 28.0%Changeup: 18.7%Cutter: 14.9%Sinker: 5.1%Slider: 2.7% FF31% · 96 mphprimary pitch FF 31%ST 28%CH 19%FC 15%SI 5%SL 3% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Perkins, Jack · 2026 arsenal snapshot 12″24″36″48″ 4-Seam Fastball: 31% usage, 1″ horizontal break, 15″ drop, 95.8 mphFF96 mphSweeper: 28% usage, 0″ horizontal break, 35″ drop, 86.2 mphST86 mphChangeup: 19% usage, 8″ horizontal break, 34″ drop, 89.5 mphCH90 mphCutter: 15% usage, 0″ horizontal break, 24″ drop, 92.6 mphFC93 mphSinker: 5% usage, 7″ horizontal break, 22″ drop, 94.8 mphSI95 mphSlider: 3% usage, 1″ horizontal break, 42″ drop, 86.0 mphSL86 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
FB 31.0% 335 102 qualified
SL 30.8% 333 108 qualified
CH 17.3% 187 105 limited sample
FC 15.9% 172 103 limited sample
SI 5.0% 54 104 limited sample
Method note

Renamed from the attempted Kirby Index after audit; true Kirby requires release-angle trajectory data.

Reference layer

Current snapshot

Age26
Height6' 1"
Weight220 lb
Debut2025-06-22
Live layer

Delta / regression

ERA Δ+1.49
K% Δ+0.034

positive regression

Regression watch

Unlucky so far. Better days ahead.

2.5σ gap
wOBA-against (actual)0.372
xwOBA-against (deserved)0.309

Perkins’s wOBA-against sits at 0.372, but the quality of contact underneath says it should be 0.309 — a gap of 0.063, 2.5 standard deviations from the MLB norm over 119 IP. The results have been worse than the process deserves; as the sample grows, expect the numbers to climb back toward the underlying level.

Mithrandir coverage

Module shelf

ModuleCardsLatestSignal
Pitching152026-09-20Changeup played up through ST/FF tunnel quality
Projection links / recent games

Available detail

Pitcher Projections 202621.7% K | 4.65 ERAProjection
2026-04-13 vs TEX4 ER / 4 K1.2 IP