Mithrandir Metrics
Player Seattle Mariners Refreshed Sep 26 06:00 AM ET
Player profile / Seattle Mariners

Leo Rivas

3B · Bats/Throws S/R · 5' 7", 150 lb · Age 28

Cards
9
Modules
2
Live Δ
yes
Club Seattle Mariners Position 3B Roster Current MLB team Status Healthy / active roster
Traditional line

Season by season

3D Swing Sim Projections
PARHHRSBAVGOBPSLGOPS
202486101703.233.333.274.607
2025111192226.244.387.333.720
2026143101802.150.270.192.462
3 Seasons3403957211.201.324.258.582
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
9
Offense
percentile
Offense9 metrics
19
Defense3 metrics
34
Speed1 metrics
53
Plate skills10 metrics
72
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
xwOBA preseason0.283
xwOBA current pace0.250
xwOBA rolling p500.269
Observed weight43%
xwOBA
0.231 0.249 0.269 0.290 0.308
wOBA
0.229 0.250 0.273 0.297 0.318
ISO
0.027 0.051 0.077 0.104 0.128
K%
20.1% 22.1% 24.4% 26.6% 28.6%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-09-26
Hitting · percentile strip
Barrel%1.2%
4
Exit velocity85.9
28
Hard-hit%19.1%
2
xBA0.262
8
xSLG0.353
4
xwOBA0.250
10 -26 vs proj
BB%12.9%
92
Bat speed61.2
1
K%27.0%
27 -21 vs proj
Defense · percentile strip
Arm Strength85.0 · 3B
32
Outs Above Avg-1.0 · 3B
27
Range Runs-1.0 · 3B
43
Baserunning · percentile strip
Sprint Speed27.6 · 3B
53
SB Success Rate100.0% · 3B
Small sample
Mithrandir+

Stuff+ and arsenal context

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

2026-09-26
Avoids Bad ChasesST 76.9% · rebadged research
97
Avoids Bad TakesHPT 29.2% · rebadged research
16
Correct Decisions67.8% · rebadged research
68
Resists Breaking - horizontalwOBA 0.265 · borderline
90
Resists Breaking - verticalwOBA 0.274 · insufficient sample
68
Resists ChangeupwOBA 0.278 · validated thin sample
56
Resists Cutters + splitterswOBA 0.321 · insufficient sample
60
Resists FastballwOBA 0.303 · validated
96
Resists SinkerwOBA 0.335 · validated
88
SEAGER+ Plate Discipline108
85
Rolling form chart

xwOBA 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 Rivas, Leo · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.302 0.250 2026-09-12: 0.2502026-09-13: 0.2502026-09-14: 0.2502026-09-18: 0.2502026-09-19: 0.2502026-09-20: 0.2502026-09-21: 0.2502026-09-22: 0.2502026-09-23: 0.2502026-09-24: 0.2502026-09-25: 0.2502026-09-26: 0.250 2026-09-12 2026-09-26 xwOBA 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.

1Pitches 2025Season 100%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 Swing Zone Profile Rivas, Leo · Aggregate zone metrics; not pitch-by-pitch locations Zone: 51%51%Chase: 16%16%Whiff: 22%22%Zone contact: 85%85%Contact: 78%78%Hard hit: 19%19% Dashed border = aggregate mixed-batter zone proxy MITHRANDIR · CHARTS
Bat tracking

Swing path, attack angle, bat speed

Aggregate Savant bat-tracking metrics; not per-swing motion capture. The full swing, with the recommended path overlaid, lives in the 3D Swing Simulator.

Watch the swing in 3D →

2026
Mithrandir Metrics BAT SPEED DISTRIBUTION Parameterized Mithrandir chart rendered as SVG for templates and exports. Bat Speed Rivas, Leo · aggregate bat speed marker 60 mph 85 mph Avg bat speed 65.0 mph Hard swing rate 0% Whiff / swing 23% MITHRANDIR · CHARTS
Pitch arsenal

Usage mix, movement map, and Stuff+ composition

2025 pitch-level arsenal aggregates; current season takes over after 100 tracked pitches across at least 2 pitch types.

Watch the pitches in 3D →

2025
Mithrandir Metrics PITCH ARSENAL DONUT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Rivas, Leo · 2025 arsenal snapshot Eephus: 100.0% EP100% · 42 mphprimary pitch EP 100% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Rivas, Leo · 2025 arsenal snapshot 6″12″18″24″ Eephus: 100% usage, 0″ horizontal break, 12″ drop, 42.1 mphEP42 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
Reference layer

Current snapshot

Age28
Height5' 7"
Weight150 lb
Debut2024-04-28
Live layer

Delta / regression

xwOBA Δ-0.041
wOBA Δ-0.018

negative regression

Regression watch

Running hot. Expect some cooling.

-0.7σ gap
wOBA (actual)0.273
xwOBA (deserved)0.250

Rivas’s wOBA sits at 0.273, but the quality of contact underneath says it should be 0.250 — a gap of 0.023, -0.7 standard deviations from the MLB norm over 163 PA. The results have outrun the underlying process; as the sample grows, expect the numbers to drift back toward the deserved level.

Mithrandir coverage

Module shelf

ModuleCardsLatestSignal
Hitting22025-10-16Impact contact was the main driver
Fielding72026-09-251 chances | 0 difficult plays | Run Exp -0.218
Projection links / recent games

Available detail

Hitter Projections 20260.292 xwOBA | 6 HRProjection
2026-04-20 vs ATH0 HR | 1 RBI / 1 Ch | 0 E1-4 | 2B, K, RBI
2026-04-17 vs TEX0 HR | 0 RBI / 1 Ch | 0 E0-2 | 2 K
2026-04-15 @ SD0 HR | 0 RBI / 4 Ch | 0 E1-3 | BB, K
2026-04-11 vs HOU0 HR | 0 RBI / 1 Ch | 0 E0-2 | 2 BB, 2 K, R
2026-04-06 @ TEX0 HR | 0 RBI / 3 Ch | 0 E0-3 | K