Mithrandir Metrics
Pitcher projection 2026 Refreshed Sep 29 06:00 AM ET
Pitcher projection / PIT · 2026

Montgomery, Mason

High-leverage relief profile with bat-miss

Primary
29.6% K%
Range
22.7% to 38.8%
Live Δ
yes
Team PIT Archetype Balanced reliever 2 Age 26 Status Healthy / active roster
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.

2026-09-29
84
Pitching
percentile
Pitching9 metrics
80
Arsenal5 metrics
88
Rolling projection

Preseason / current pace / Bayesian update

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

2026-09-29
ERA preseason4.06
ERA current pace2.55
ERA rolling p503.24
Observed weight54%
ERA
1.30 2.22 3.24 4.26 5.18
FIP
2.34 2.60 2.90 3.20 3.47
K%
30.0% 32.0% 34.2% 36.4% 38.4%
BB%
7.2% 8.5% 9.9% 11.4% 12.6%
Current percentile strip

Actual percentile with projection tick

100th = best in MLB.

2026-09-29
Pitching · percentile strip
WHIP1.04
91
ERA2.55
91
BB%9.5%
44
K%37.5%
100
xwOBA allowed0.247
97 +36 vs proj
Barrel allowed6.0%
74 +40 vs proj
Fastball velo98.6
97
Hard-hit allowed41.3%
30
Whiff%31.0%
95
Mithrandir+

Stuff+ and arsenal context

Stuff+ appears when the current pitch-event scoring artifact includes this pitcher; Arsenal Decomposition remains descriptive support under Stuff+.

2026-09-29
Fastball Stuff+110
96
Mithrandir Stuff+110
99
Curveball Stuff+104
70
Sinker Stuff+109
93
Slider Stuff+106
82
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.

5Pitches 2026Season 46%Top usage
ride armside gloveside +Arsenal gap +Shape contrast
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 Montgomery, Mason · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.313 0.247 2026-09-18: 0.2512026-09-19: 0.2512026-09-20: 0.2512026-09-21: 0.2502026-09-22: 0.2502026-09-23: 0.2502026-09-24: 0.2502026-09-25: 0.2502026-09-26: 0.2472026-09-27: 0.2492026-09-28: 0.2472026-09-29: 0.247 2026-09-18 2026-09-29 xwOBA allowed MITHRANDIR · CHARTS
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 Montgomery, Mason · Aggregate zone metrics; not pitch-by-pitch locations Edge: 35%35%Zone: 48%48%Whiff: 31%31%Called strike: 16%16%First pitch strike: 53%53%Hard hit allowed: 41%41% 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.

2026
Mithrandir Metrics PITCH ARSENAL DONUT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Montgomery, Mason · 2026 arsenal snapshot 4-Seam Fastball: 46.4%Sinker: 23.7%Curveball: 13.9%Slider: 13.7%Changeup: 2.2% FF46% · 98 mphprimary pitch FF 46%SI 24%CU 14%SL 14%CH 2% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Montgomery, Mason · 2026 arsenal snapshot 12″24″36″48″ 4-Seam Fastball: 46% usage, 1″ horizontal break, 10″ drop, 98.5 mphFF98 mphSinker: 24% usage, 6″ horizontal break, 13″ drop, 98.7 mphSI99 mphCurveball: 14% usage, 1″ horizontal break, 43″ drop, 86.5 mphCU86 mphSlider: 14% usage, 1″ horizontal break, 32″ drop, 89.6 mphSL90 mphChangeup: 2% usage, 9″ horizontal break, 23″ drop, 90.2 mphCH90 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
FB 49.0% 332 110 qualified
SI 24.1% 163 109 limited sample
CB 13.6% 92 104 limited sample
SL 12.3% 83 106 limited sample
CH 1.0% 7 117 limited sample
Method note

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

Model read

Projection notes

1
templated note
Plays better against lefties right now (0.279 vs 0.305 xwOBA allowed split).
pitcher
2
templated note
Volume stays relief-shaped even when the bat-miss traits are strong.
pitcher
3
templated note
Home park gives the run-prevention profile a small HR cushion.
pitcher
4
templated note
Primary mix entering the season: 4-Seam Fastball 67%, Slider 33%.
pitcher
Live context

Current-season signal

ERA Δ-1.45
K% Δ+0.079
Sample70.3 IP

positive regression

Projection table

Point projection and range

MetricPointRangeHalf-width
Innings33.5----
Batters Faced154----
K%29.6%22.7% to 38.8%+/- 8.1%
BB%10.5%5.8% to 16.3%+/- 5.3%
Whiff%29.7%25.3% to 38.3%+/- 6.5%
HR/91.030.35 to 1.92+/- 0.78
xwOBA Against0.3050.252 to 0.389+/- 0.069
Barrel% Allowed8.4%3.6% to 14.2%+/- 5.3%
ERA4.001.98 to 7.44+/- 2.73
FIP3.661.88 to 3.48+/- 0.80
WHIP1.4221.088 to 2.088+/- 0.500
Platoon / Shape
vs LHH

99 career BF

xwOBA0.279
K%29.1%
BB%10.8%
Barrel8.0%
vs RHH

158 career BF

xwOBA0.305
K%26.6%
BB%10.9%
Barrel11.2%