Mithrandir Metrics
Player San Francisco Giants Refreshed Sep 27 06:00 AM ET
Player profile / San Francisco Giants

Christian Koss

SS · Bats/Throws R/R · 6' 1", 185 lb · Age 28

Cards
28
Modules
1
Live Δ
yes
Club San Francisco Giants Position SS Roster Current MLB team Status Healthy / active roster
Traditional line

Season by season

3D Swing Sim Projections
PARHHRSBAVGOBPSLGOPS
2025191254634.264.309.368.677
2026221274445.217.257.305.562
2 Seasons412529079.239.281.334.615
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
13
Offense
percentile
Offense9 metrics
14
Defense3 metrics
48
Speed3 metrics
71
Plate skills11 metrics
44
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
xwOBA preseason0.291
xwOBA current pace0.239
xwOBA rolling p500.264
Observed weight52%
xwOBA
0.227 0.245 0.264 0.284 0.302
wOBA
0.262 0.280 0.300 0.320 0.338
ISO
0.067 0.086 0.108 0.129 0.148
K%
20.8% 22.4% 24.2% 25.9% 27.5%
Live percentile strip

Current traits vs projection tick

100th = best in MLB.

2026-09-27
Hitting · percentile strip
Barrel%3.0%
23
Exit velocity80.5
3
Hard-hit%27.0%
10 -19 vs proj
xBA0.293
21
xSLG0.396
12
xwOBA0.239
6 -29 vs proj
BB%4.3%
9
Bat speed65.7
10
K%25.6%
35 -21 vs proj
Defense · percentile strip
Arm Strength84.9 · SS
30
Outs Above Avg0.0 · SS
47
Range Runs1.2 · SS
67
Baserunning · percentile strip
Bolts3.0 · SS
32
SB Success Rate100.0% · SS
94
Sprint Speed28.9 · SS
88
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
Avoids Bad ChasesST 56.7% · rebadged research
12
Avoids Bad TakesHPT 28.8% · rebadged research
19
Correct Decisions61.7% · rebadged research
14
Mithrandir Stuff+88
7
Resists Breaking - horizontalwOBA 0.294 · borderline
38
Resists Breaking - verticalwOBA 0.268 · insufficient sample
83
Resists ChangeupwOBA 0.256 · validated thin sample
93
Resists Cutters + splitterswOBA 0.316 · insufficient sample
75
Resists FastballwOBA 0.325 · validated
76
Resists SinkerwOBA 0.356 · validated
53
SEAGER+ Plate Discipline89
9
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 Koss, Christian · Live snapshot series; true 50/100 PA windows require PA-level logs LG AVG 0.302 0.239 2026-09-13: 0.2562026-09-14: 0.2552026-09-18: 0.2572026-09-19: 0.2542026-09-20: 0.2542026-09-21: 0.2492026-09-22: 0.2502026-09-23: 0.2482026-09-24: 0.2462026-09-25: 0.2462026-09-26: 0.2432026-09-27: 0.239 2026-09-13 2026-09-27 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.

3Pitches 2025Season 88%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 Koss, Christian · Aggregate zone metrics; not pitch-by-pitch locations Zone: 47%47%Chase: 40%40%Whiff: 28%28%Zone contact: 82%82%Contact: 72%72%Hard hit: 27%27% Dashed border = aggregate mixed-batter zone proxy 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 Koss, Christian · 2025 arsenal snapshot Eephus: 88.1%Other: 7.1%Knuckleball: 4.8% EP88% · 51 mphprimary pitch EP 88%FA 7%KN 5% MITHRANDIR · CHARTS
Mithrandir Metrics PITCH MOVEMENT Parameterized Mithrandir chart rendered as SVG for templates and exports. Pitch Arsenal Koss, Christian · 2025 arsenal snapshot 6″12″18″24″ Eephus: 88% usage, 0″ horizontal break, 8″ drop, 51.1 mphEP51 mphOther: 7% usage, 1″ horizontal break, 2″ drop, 83.6 mphFA84 mphKnuckleball: 5% usage, 0″ horizontal break, 7″ drop, 58.9 mphKN59 mph less drop ↑ more drop ↓ · horizontal break ↔ · dot size = usage · break incl. gravity MITHRANDIR · CHARTS
Reference layer

Current snapshot

Age28
Height6' 1"
Weight185 lb
Debut2025-04-01
Live layer

Delta / regression

xwOBA Δ-0.051
wOBA Δ+0.010

negative regression

Regression watch

Running hot. Expect some cooling.

-1.9σ gap
wOBA (actual)0.300
xwOBA (deserved)0.239

Koss’s wOBA sits at 0.300, but the quality of contact underneath says it should be 0.239 — a gap of 0.061, -1.9 standard deviations from the MLB norm over 234 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
Fielding282026-09-261 chances | 0 difficult plays | Run Exp +0.156
Projection links / recent games

Available detail

2026-08-15 vs COL0 HR | 0 RBI / 2 Ch | 0 E1-4 | 2 K, R
2026-04-12 @ BAL0 HR | 0 RBI / 4 Ch | 0 E0-3
2026-04-11 @ BAL0 HR | 0 RBI / 0 Ch | 0 E1-1 | 2B
2026-04-08 vs PHI0 HR | 0 RBI / 1 Ch | 0 E0-3
2026-04-04 vs NYM0 HR | 0 RBI / 0 Ch | 0 E0 H in 0 AB