Mithrandir Metrics
Player Seattle Mariners Refreshed Jul 17 06:00 AM ET
Player profile / Seattle Mariners

George Kirby

P · Bats/Throws R/R · 6' 4", 215 lb · Age 28

Cards
22
Modules
1
Live Δ
yes
Club Seattle Mariners Position P Roster Active Status Healthy / active roster
Traditional line

Season by season

3D Pitch Lab Projections
WLERAGGSSVIPSOWHIP
202414113.5333330191.01791.07
20251084.2123230126.01371.19
2026783.7618180110.0981.32
5 Seasons52423.611301300747.27191.14
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.

2026-07-17
58
Pitching
percentile
Pitching9 metrics
54
Arsenal7 metrics
74
Rolling projection

Preseason / current pace / Bayesian update

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

2026-07-17
ERA preseason3.59
ERA current pace3.76
ERA rolling p503.70
Observed weight68%
ERA
2.64 3.14 3.70 4.26 4.77
FIP
2.89 3.17 3.48 3.80 4.08
K%
19.4% 20.6% 22.0% 23.3% 24.5%
BB%
4.2% 4.7% 5.3% 5.9% 6.4%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-07-17
Pitching · percentile strip
WHIP1.36
43
ERA3.76
56
BB%5.4%
93
K%21.2%
41 -21 vs proj
xwOBA allowed0.305
59
Barrel allowed7.2%
59 +19 vs proj
Fastball velo96.8
84
Hard-hit allowed43.9%
19
Whiff%21.0%
34 -17 vs proj
Mithrandir+

Stuff+ and arsenal context

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

2026-07-17
Fastball Stuff+107
85
Mithrandir Stuff+108
94
Sinker Stuff+108
93
Slider Stuff+109
92
Changeup Stuff+106
76
Curveball Stuff+102
48
Cutter Stuff+99
27
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 Kirby, George · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.314 0.305 2026-07-06: 0.3002026-07-07: 0.3002026-07-08: 0.3002026-07-09: 0.3002026-07-10: 0.3052026-07-11: 0.3052026-07-12: 0.3052026-07-13: 0.3052026-07-14: 0.3052026-07-15: 0.3052026-07-16: 0.3052026-07-17: 0.305 2026-07-06 2026-07-17 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 30%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 Kirby, George · Aggregate zone metrics; not pitch-by-pitch locations Edge: 38%38%Zone: 50%50%Whiff: 21%21%Called strike: 15%15%First pitch strike: 51%51%Hard hit allowed: 44%44% 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 Kirby, George · 2026 arsenal snapshot Sweeper: 29.9%4-Seam Fastball: 28.5%Sinker: 21.2%Knuckle Curve: 9.8%Changeup: 7.6%Cutter: 3.0% ST30% · 87 mphprimary pitch ST 30%FF 29%SI 21%KC 10%CH 8%FC 3% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Kirby, George · 2026 arsenal snapshot 15″30″45″60″ Sweeper: 30% usage, 2″ horizontal break, 40″ drop, 87.2 mphST87 mph4-Seam Fastball: 29% usage, 2″ horizontal break, 16″ drop, 96.7 mphFF97 mphSinker: 21% usage, 9″ horizontal break, 21″ drop, 96.9 mphSI97 mphKnuckle Curve: 10% usage, 8″ horizontal break, 53″ drop, 83.8 mphKC84 mphChangeup: 8% usage, 7″ horizontal break, 30″ drop, 88.7 mphCH89 mphCutter: 3% usage, 1″ horizontal break, 21″ drop, 93.2 mphFC93 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
FB 31.3% 319 107 qualified
SL 27.2% 277 109 qualified
SI 19.6% 200 108 qualified
CB 10.3% 105 102 limited sample
CH 7.5% 76 106 limited sample
FC 4.1% 42 99 limited sample
Method note

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

Reference layer

Current snapshot

Age28
Height6' 4"
Weight215 lb
Debut2022-05-08
Live layer

Delta / regression

ERA Δ+0.32
K% Δ-0.030

positive regression

Regression watch

Unlucky so far. Better days ahead.

2.4σ gap
wOBA-against (actual)0.368
xwOBA-against (deserved)0.305

Kirby’s wOBA-against sits at 0.368, but the quality of contact underneath says it should be 0.305 — a gap of 0.063, 2.4 standard deviations from the MLB norm over 118 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
Pitching222026-07-08Sweeper played up through ST/SI tunnel quality
Projection links / recent games

Available detail

Pitcher Projections 202624.2% K | 3.44 ERAProjection
2026-04-13 vs HOU2 ER / 6 K7.2 IP
2026-04-07 @ TEX3 ER / 4 K8.0 IP
2026-04-01 vs NYY4 ER / 6 K6.0 IP
2026-03-27 vs CLE1 ER / 6 K6.0 IP