Walk-Off Victory Extra-Innings Win Probability Workbench San Francisco 5, St. Louis 4

San Francisco Walk-Off Explorer: 11th Inning Leverage

Batter: Shay Whitcomb Play: Game-Ending RBI Single (Shortstop Side) Historical Context: September 8, 2026 vs. St. Louis Cardinals Reported by: @NBCSports (8.4K impressions)
D3.js Inning Leverage Matrix (Regulation to Extras)
Interactive Step Navigation
11th Inning Walk-Off Leverage: St. Louis was held scoreless in the top of the 11th. With the automatic runner positioned on 2nd base and advancing to 3rd on a productive groundout (1 out), San Francisco held a 74.5% situational win expectancy before Shay Whitcomb drove a single through the shortstop side to claim the 5-4 victory (100% WPA).
CALC Counterfactual Play Simulator
Live Probability Engine
74.5%
Bottom 11th • 1 Out • Runner on 3rd
Leverage Index (LI)
3.42 High
1B 2B 3B
Base-Out State Runner on 3rd, 1 Out
Walk-Off Delta (WPA) +25.5% (Win)
Shay Whitcomb Walk-Off Play Breakdown 1st Career Game-Ending RBI
Top 11
Defensive Hold (Tied 4-4): SF relief staff strangles St. Louis ghost runner at 2nd via groundout and two strikeouts, keeping win expectancy intact at 58.2% entering the home half.
Bot 11
Productive Grounder (1 Out): Automatic ghost runner advances cleanly from second to third base on an infield groundout to right side. Win expectancy climbs to 74.5%.
WALK-OFF
Shay Whitcomb Clutch RBI Single: Ground ball slashed deep through the shortstop side. The runner scores effortlessly from 3rd base. San Francisco wins 5-4. Win expectancy hits 100%.
HISTORICAL Extra-Innings Baseline Matrix
MLB Extras Empirical Model

Under modern extra-inning rules (starting with runner on second base), the home team possesses a persistent statistical advantage when the visiting team fails to score in the top half:

  • Runner on 3rd, 0 Outs: 85.0% Home Win Expectancy
  • Runner on 3rd, 1 Out (Whitcomb Context): 74.5% Home Win Expectancy
  • Runner on 3rd, 2 Outs: 48.0% Home Win Expectancy
  • Bases Loaded, 1 Out: 81.2% Home Win Expectancy
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