Mithrandir Metrics
Pitcher projection 2026 Refreshed Sep 26 06:00 AM ET
Pitcher projection / TOR · 2026

Arrighetti, Spencer

Run-prevention profile built on workable command

Primary
24.1% K%
Range
21.2% to 32.4%
Live Δ
yes
Team TOR Archetype Volatile contact Age 26 Status Out / inactive
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
27
Pitching
percentile
Pitching9 metrics
36
Arsenal7 metrics
55
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 preseason4.13
ERA current pace4.90
ERA rolling p504.65
Observed weight67%
ERA
3.30 3.94 4.65 5.36 6.00
FIP
3.78 4.27 4.82 5.37 5.86
K%
20.2% 21.4% 22.7% 23.9% 25.1%
BB%
10.2% 11.0% 11.9% 12.8% 13.6%
Current percentile strip

Actual percentile with projection tick

100th = best in MLB.

2026-09-26
Pitching · percentile strip
WHIP1.41
35
ERA4.90
29
BB%13.0%
11 -29 vs proj
K%21.5%
45 -21 vs proj
xwOBA allowed0.349
15
Barrel allowed9.2%
23
Fastball velo92.3
19
Hard-hit allowed31.6%
92
Whiff%23.3%
56
Mithrandir+

Stuff+ and arsenal context

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

2026-09-26
Curveball Stuff+102
40
Fastball Stuff+105
73
Mithrandir Stuff+102
52
Changeup Stuff+96
17
Cutter Stuff+110
100
Sinker Stuff+105
70
Slider Stuff+100
35
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.

7Pitches 2026Season 34%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 Arrighetti, Spencer · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.313 0.349 2026-09-12: 0.3502026-09-13: 0.3482026-09-14: 0.3482026-09-18: 0.3482026-09-19: 0.3482026-09-20: 0.3482026-09-21: 0.3492026-09-22: 0.3492026-09-23: 0.3492026-09-24: 0.3492026-09-25: 0.3492026-09-26: 0.349 2026-09-12 2026-09-26 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 Arrighetti, Spencer · Aggregate zone metrics; not pitch-by-pitch locations Edge: 38%38%Zone: 45%45%Whiff: 23%23%Called strike: 18%18%First pitch strike: 46%46%Hard hit allowed: 32%32% 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 Arrighetti, Spencer · 2026 arsenal snapshot Curveball: 34.2%4-Seam Fastball: 28.1%Sweeper: 11.6%Sinker: 10.5%Changeup: 8.0%Cutter: 6.7% CU34% · 76 mphprimary pitch CU 34%FF 28%ST 12%SI 11%CH 8%FC 7% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Arrighetti, Spencer · 2026 arsenal snapshot 15″30″45″60″ Curveball: 34% usage, 6″ horizontal break, 54″ drop, 76.5 mphCU76 mph4-Seam Fastball: 28% usage, 3″ horizontal break, 18″ drop, 92.4 mphFF92 mphSweeper: 12% usage, 4″ horizontal break, 41″ drop, 79.7 mphST80 mphSinker: 11% usage, 9″ horizontal break, 23″ drop, 92.1 mphSI92 mphChangeup: 8% usage, 12″ horizontal break, 34″ drop, 84.2 mphCH84 mphCutter: 7% usage, 0″ horizontal break, 25″ drop, 87.8 mphFC88 mphSlider: 1% usage, 7″ horizontal break, 36″ drop, 82.2 mphSL82 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
CB 33.5% 413 102 qualified
FB 26.2% 322 105 qualified
SL 13.0% 160 100 limited sample
SI 10.1% 124 105 limited sample
CH 9.0% 111 96 limited sample
FC 8.2% 101 110 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
Home park slightly inflates the home-run risk band.
pitcher
2
templated note
Primary mix entering the season: 4-Seam Fastball 32%, Curveball 22%, Cutter 14%.
pitcher
Live context

Current-season signal

ERA Δ+0.60
K% Δ-0.026
Sample108.7 IP

negative regression

Projection table

Point projection and range

MetricPointRangeHalf-width
Innings69.3----
Batters Faced311----
K%24.1%21.2% to 32.4%+/- 5.6%
BB%9.8%6.5% to 13.0%+/- 3.2%
Whiff%24.4%20.7% to 31.6%+/- 5.4%
HR/91.470.60 to 1.94+/- 0.67
xwOBA Against0.3330.262 to 0.352+/- 0.045
Barrel% Allowed8.4%5.2% to 11.3%+/- 3.1%
ERA4.302.33 to 5.95+/- 1.81
FIP4.242.61 to 5.38+/- 1.39
WHIP1.3661.058 to 1.628+/- 0.285
Platoon / Shape
vs LHH

451 career BF

xwOBA0.303
K%26.5%
BB%11.8%
Barrel8.7%
vs RHH

390 career BF

xwOBA0.286
K%24.9%
BB%8.4%
Barrel7.3%