Mithrandir Metrics
Player Kansas City Royals Refreshed Sep 27 06:00 AM ET
Player profile / Kansas City Royals

Spencer Bivens

P · Bats/Throws R/R · 6' 4", 220 lb · Age 32

Cards
2
Modules
1
Live Δ
--
Club Kansas City Royals Position P Roster Current MLB team Status Healthy / active roster
Traditional line

Season by season

3D Pitch Lab Projections
WLERAGGSSVIPSOWHIP
2024313.14272148.2371.19
2025434.00540381.0611.33
2026009.396007.2122.48
3 Seasons744.008724137.11101.35
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.

2026-09-27
76
Pitching
percentile
Arsenal3 metrics
76
Rolling projection

Preseason / current pace / Bayesian update

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

2026-09-27
ERA preseason4.44
ERA current pace10.29
ERA rolling p505.55
Observed weight19%
ERA
3.71 4.58 5.55 6.51 7.39
FIP
2.78 3.41 4.12 4.82 5.46
K%
14.7% 17.0% 19.4% 21.9% 24.2%
BB%
4.5% 6.1% 7.8% 9.5% 11.1%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-09-27
Mithrandir+

Stuff+ and arsenal context

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

2026-09-27
Mithrandir Stuff+103
57
Sinker Stuff+111
97
Slider Stuff+104
73
Rolling form chart

xwOBA allowed snapshot line

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

0 snapshots
No chart yet

No Live State xwOBA snapshots are available for this player.

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 38%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 Bivens, Spencer · Aggregate zone metrics; not pitch-by-pitch locations Edge: 37%37%Zone: 49%49%Whiff: 21%21%Called strike: 19%19%First pitch strike: 52%52%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.

Watch the pitches in 3D →

2026
Mithrandir Metrics PITCH ARSENAL DONUT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Bivens, Spencer · 2026 arsenal snapshot Sinker: 38.1%4-Seam Fastball: 19.9%Sweeper: 19.9%Changeup: 9.1%Cutter: 8.7%Curveball: 2.6% SI38% · 95 mphprimary pitch SI 38%FF 20%ST 20%CH 9%FC 9%CU 3% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Bivens, Spencer · 2026 arsenal snapshot 12″24″36″48″ Sinker: 38% usage, 7″ horizontal break, 27″ drop, 94.6 mphSI95 mph4-Seam Fastball: 20% usage, 4″ horizontal break, 19″ drop, 94.5 mphFF94 mphSweeper: 20% usage, 7″ horizontal break, 36″ drop, 81.5 mphST81 mphChangeup: 9% usage, 9″ horizontal break, 36″ drop, 87.6 mphCH88 mphCutter: 9% usage, 1″ horizontal break, 28″ drop, 89.1 mphFC89 mphCurveball: 3% usage, 7″ horizontal break, 44″ drop, 81.8 mphCU82 mphSlurve: 2% usage, 2″ horizontal break, 46″ drop, 81.1 mphSV81 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
SI 34.4% 11 111 limited sample
SL 34.4% 11 104 limited sample
FB 15.6% 5 91 limited sample
CH 12.5% 4 80 limited sample
FC 3.1% 1 118 limited sample
Method note

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

Reference layer

Current snapshot

Age32
Height6' 4"
Weight220 lb
Debut2024-06-16
Live layer

Delta / regression

No Live State delta is available for this profile yet.

Mithrandir coverage

Module shelf

ModuleCardsLatestSignal
Pitching22026-03-23Stuff and strike quality carried the outing
Projection links / recent games

Available detail

Pitcher Projections 202618.6% K | 4.36 ERAProjection
2026-03-20 @ TEX0 ER / 1 K2.0 IP
2026-03-11 @ KC0 ER / 3 K2.0 IP