Mithrandir Metrics
Pitcher projection 2026 Refreshed Sep 5 06:00 AM ET
Pitcher projection / PIT · 2026

Montgomery, Mason

High-leverage relief profile with bat-miss

Primary
29.5% 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.

2026-09-05
82
Pitching
percentile
Pitching9 metrics
77
Arsenal5 metrics
89
Rolling projection

Preseason / current pace / Bayesian update

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

2026-09-05
ERA preseason4.06
ERA current pace3.02
ERA rolling p503.53
Observed weight51%
ERA
1.60 2.52 3.53 4.55 5.46
FIP
2.33 2.60 2.90 3.19 3.46
K%
29.6% 31.7% 34.0% 36.4% 38.5%
BB%
7.0% 8.4% 9.9% 11.4% 12.8%
Current percentile strip

Actual percentile with projection tick

100th = best in MLB.

2026-09-05
Pitching · percentile strip
WHIP1.06
88
ERA3.02
81
BB%9.3%
45
K%37.8%
99
xwOBA allowed0.250
96 +39 vs proj
Barrel allowed7.0%
57 +23 vs proj
Fastball velo98.6
97
Hard-hit allowed40.3%
36
Whiff%31.1%
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+.

2026-09-05
Fastball Stuff+110
96
Mithrandir Stuff+110
98
Curveball Stuff+103
65
Sinker Stuff+110
97
Slider Stuff+107
91
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 50%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 0.250 2026-08-25: 0.2492026-08-26: 0.2492026-08-27: 0.2482026-08-28: 0.2482026-08-29: 0.2482026-08-30: 0.2472026-08-31: 0.2472026-09-01: 0.2472026-09-02: 0.2522026-09-03: 0.2522026-09-04: 0.2502026-09-05: 0.250 2026-08-25 2026-09-05 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: 40%40% 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: 50.0%Sinker: 17.8%Slider: 14.9%Curveball: 14.7%Changeup: 2.6% FF50% · 98 mphprimary pitch FF 50%SI 18%SL 15%CU 15%CH 3% 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: 50% usage, 1″ horizontal break, 10″ drop, 98.4 mphFF98 mphSinker: 18% usage, 5″ horizontal break, 13″ drop, 98.9 mphSI99 mphSlider: 15% usage, 1″ horizontal break, 32″ drop, 89.6 mphSL90 mphCurveball: 15% usage, 1″ horizontal break, 43″ drop, 86.6 mphCU87 mphChangeup: 3% 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 55.2% 303 110 qualified
SI 15.3% 84 110 limited sample
CB 14.2% 78 103 limited sample
SL 14.0% 77 107 limited sample
CH 1.3% 7 115 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-1.01
K% Δ+0.083
Sample60.3 IP

positive regression

Projection table

Point projection and range

MetricPointRangeHalf-width
Innings34.3----
Batters Faced157----
K%29.5%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%
ERA4.031.98 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%