Mithrandir Metrics
Player St. Louis Cardinals Refreshed Jun 1 06:00 AM ET
Player profile / St. Louis Cardinals

JoJo Romero

P profile with live context, projection links, and Mithrandir card history when available.

Cards
0
Modules
0
Live Δ
yes
Club St. Louis Cardinals Position P Roster Active Status Healthy / active roster
Rolling projection

Preseason / current pace / Bayesian update

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

2026-06-01
ERA preseason3.63
ERA current pace2.81
ERA rolling p503.37
Observed weight32%
ERA
1.81 2.55 3.37 4.19 4.93
FIP
1.75 2.61 3.57 4.53 5.39
K%
18.5% 20.7% 23.2% 25.6% 27.8%
BB%
5.6% 6.9% 8.4% 9.9% 11.2%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-06-01
Pitching · percentile strip
BB%8.7%
51
Barrel allowed6.7%
66
Fastball velo93.9
41
Hard-hit allowed45.3%
15
K%24.3%
62
Whiff%22.0%
42 -26 vs proj
xwOBA allowed0.331
36 -18 vs proj
Mithrandir+

Stuff+ and arsenal context

Stuff+ appears when the current pitch-event scoring artifact includes this pitcher; missing coverage is shown explicitly.

2026-06-01
Mithrandir Stuff+104
71
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 Romero, JoJo · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.314 2026-05-17: 0.3342026-05-19: 0.3342026-05-21: 0.3402026-05-23: 0.3402026-05-24: 0.3402026-05-25: 0.3402026-05-26: 0.3402026-05-28: 0.3342026-05-29: 0.3342026-05-30: 0.3342026-05-31: 0.3312026-06-01: 0.331 2026-05-17 2026-06-01 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.

4Pitches 2026Season 43%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 Romero, JoJo · Aggregate zone metrics; not pitch-by-pitch locations Edge: 37%37%Zone: 45%45%Whiff: 22%22%Called strike: 22%22%First pitch strike: 49%49%Hard hit allowed: 45%45% 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 Romero, JoJo · 2026 arsenal snapshot Sinker: 42.8%Sweeper: 37.4%Changeup: 17.6%4-Seam Fastball: 2.2% MIX SI 43%ST 37%CH 18%FF 2% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Romero, JoJo · 2026 arsenal snapshot SI: HB -0.3, IVB 2.5SIST: HB -0.2, IVB 3.4STCH: HB -1.0, IVB 3.1CHFF: HB -0.2, IVB 1.5FF horizontal break IVB MITHRANDIR · CHARTS
PitchUsagePitchesStuff+Status
SI 42.3% 182 101 limited sample
SL 37.2% 160 113 limited sample
CH 18.1% 78 93 limited sample
FB 2.3% 10 102 limited sample
Method note

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

Reference layer

Current snapshot

Age29
Height5' 11"
Weight215 lb
Debut2020-08-21
Live layer

Delta / regression

ERA Δ-0.80
K% Δ+0.020
Mithrandir coverage

Module shelf

ModuleCardsLatestSignal
No Mithrandir card history is available for this player yet.
Projection links / recent games

Available detail

Pitcher Projections 202622.4% K | 3.61 ERAProjection
2026-04-17 @ HOU0 ER / 0 K1.0 IP
2026-04-15 vs CLE0 ER / 1 K1.1 IP
2026-04-14 vs CLE0 ER / 0 K1.1 IP
2026-04-06 @ WSH0 ER / 0 K1.0 IP
2026-04-05 @ DET0 ER / 1 K1.2 IP