Mithrandir Metrics
STL 2026-09-08 Refreshed Sep 11 06:00 AM ET
Section III · Betting · Player detail · 2026-09-08

Iván Herrera

STL · Hitter · bats R · age 26
IN · 2 Negative regression Pitcher-Friendly
MatchupSTL vs SFLanden Roupp
Sample1217.0career MLB AB
PROPS 2 available PERCENTILES 20 rows LINEUPS confirmed artifact NO PROSE templated rows only
Strikeouts · Palantir calibration review Last 14d ECE 0.060, 14d stable. This flags probability calibration, not a blanket model failure.
Strikeouts · Valinor calibration review Last 14d ECE 0.063, 14d stable. This flags probability calibration, not a blanket model failure.
Hits · Palantir calibration review Last 14d ECE 0.062, 14d error rising. This flags probability calibration, not a blanket model failure.
Tonight's props · all markets for this player
Home Run 0.5
P 11.8
F 12.0
V 10.5
Model 12.0% Market 12.6% Gap -0.9pp
DraftKings 670 tracking Open board
Total Bases 0.5
P 59.2
F -- in progress
V -- in progress
INSUFFICIENT LANES
Model 71.8% Market 72.6% Gap +13.4pp
BetMGM -265 tracking Open board
Hits --
Hits · tracking

No production board publishes this player-market cell today.

RBI --
RBI · no production board

No production board publishes this player-market cell today.

Underlying skill · actual percentile with projection tick

Percentile strip

100th = best in MLB
Hitting · percentile strip
Barrel%4.0%
36 -33 vs proj
Exit velocity89.3
67
Hard-hit%40.8%
62 -16 vs proj
xBA0.319
51
xSLG0.486
44
xwOBA0.333
79
BB%10.7%
76 +18 vs proj
Bat speed71.3
74
K%18.3%
75
Defense · percentile strip
Blocking Runs0.3 · C
66
Catcher Throwing-3.9 · C
1
Framing Runs-1.0 · C
36
Pop Time2.0 · C
13
Baserunning · percentile strip
Base Running Runs-2.1 · DH
13
SB Success Rate100.0% · DH
94
Sprint Speed26.1 · DH
19
Mithrandir+ · percentile strip
Avoids Bad ChasesST 68.5%
66
Avoids Bad TakesHPT 27.4%
29
Correct Decisions65.3%
42
SEAGER+ Plate Discipline101
55

Context

projection · regression · matchup
Projected range0.324 to 0.383
RegressionNegative · -0.021
Opposing pitcherLanden Roupp
EnvironmentPitcher-Friendly
Lane calibration receipts
Lane Health 2026-09-11
Palantir 19641 props Brier 0.118 ECE 0.006 14d stable
Fangorn 19641 props Brier 0.118 ECE 0.006 14d stable
Valinor 13965 props Brier 0.113 ECE 0.003 14d stable
Palantir 1750 props Brier 0.248 ECE 0.010 14d stable
Fangorn 53 props Brier 0.257 ECE 0.119 sample building
Valinor 1246 props Brier 0.249 ECE 0.020 14d stable
Palantir 9432 props Brier 0.238 ECE 0.046 14d stable
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir 756 props Brier 0.167 ECE 0.038 14d error rising
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir 986 props Brier 0.256 ECE 0.054 14d stable
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir tracking in progress (0 logged)
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)