The Red Sox have a clear edge because their starting pitching is stronger overall. The Yankees have the advantage in defense and how this park suits them, which keeps the matchup close.
Why 55%?
8 of 15 categories could be scored from the data on file. The 7 unscored categories are listed openly rather than guessed at, and their weight is shared across the categories that could be measured.
Offense
The home club has a slight edge in offense (100 vs 100 wRC+).
- Team wRC+ (away) 100 MLB Stats API
- Team wRC+ (home) 100 MLB Stats API
- Team OPS (away) .717 MLB Stats API
- Team OPS (home) .720 MLB Stats API
- Runs per game (away) 4.27 MLB Stats API
- Runs per game (home) 4.59 MLB Stats API
- Hard-hit % (away) Unavailable MLB Stats API
- Hard-hit % (home) Unavailable MLB Stats API
Starting Pitcher
The away club has a strong edge in starting pitching (3.15 vs 3.93 FIP).
- Starter FIP (away) 3.15 MLB Stats API
- Starter FIP (home) 3.93 MLB Stats API
- K-BB% (away) 15.4 MLB Stats API
- K-BB% (home) 15.4 MLB Stats API
- WHIP (away) 1.19 MLB Stats API
- WHIP (home) 1.37 MLB Stats API
- Opponent OPS (away) .639 MLB Stats API
- Opponent OPS (home) .756 MLB Stats API
Bullpen
Bullpen splits have not been imported for both clubs.
Lineup / Platoon
Neither club has a meaningful edge in platoon matchups (.733 vs .733 OPS in their stronger split). Starter handedness and confirmed lineups are not wired up, so this is a club-level split rather than a true lineup-versus-starter read.
- OPS vs LHP (away) .733 MLB Stats API
- OPS vs RHP (away) .711 MLB Stats API
- OPS vs LHP (home) .733 MLB Stats API
- OPS vs RHP (home) .714 MLB Stats API
- Confirmed lineup Unavailable
- Platoon advantage count Unavailable
- WAR missing from lineup Unavailable
Pitch-Type Matchup
Pitch usage and hitter results by pitch type are not in the daily snapshot yet, so this category is not scored.
Defense
The home club has a clear edge in defense (.708 vs .728 defensive efficiency). DRS and UZR have no free public source and are left out rather than estimated.
- Defensive efficiency (away) .708 MLB Stats API
- Defensive efficiency (home) .728 MLB Stats API
- Outs Above Average (away) 20 MLB Stats API
- Outs Above Average (home) 3 MLB Stats API
- Defensive Runs Saved Unavailable
- UZR Unavailable
Baserunning
Needs full player-level import for both clubs; only teams with individual hitter snapshots roll up to a team baserunning total.
Recent Form
Neither club has a meaningful edge in recent form (5-5 vs 5-5 over ten games). Ten games is a small sample, which is why this is weighted lightly.
- Last 10 (away) 5-5 MLB Stats API
- Last 10 (home) 5-5 MLB Stats API
- Last 5 run differential (away) Unavailable MLB Stats API
- Last 5 run differential (home) Unavailable MLB Stats API
- Streak (away) W2 MLB Stats API
- Streak (home) W1 MLB Stats API
Ballpark Fit
Yankee Stadium plays big for power (114 home run factor). The home club has a slight edge in how this park suits them (.150 vs .170 ISO).
- Run park factor 103 MLB park-factor baseline (multi-year estimate)
- Home run park factor 114 MLB park-factor baseline (multi-year estimate)
- Double park factor 96 MLB park-factor baseline (multi-year estimate)
- Team ISO (away) .150 MLB Stats API
- Team ISO (home) .170 MLB Stats API
Weather
No weather feed is wired up, so temperature, wind and carry are not scored.
Rest / Fatigue
Travel, days rest and schedule density are not tracked yet.
Injuries
There is no injured-list feed, so missing WAR is not scored.
Historical Calibration
Judged against how this season has actually gone, the rest of the model looks a little low on the home club, by about 2 points. That read is backtested over 52 completed games at 56% accuracy.
- Backtest sample size 52 games NumSOX backtest
- Backtest accuracy 55.8% NumSOX backtest
- Brier score 0.254 NumSOX backtest
- Calibration adjustment -2 pts to the Red Sox NumSOX backtest
Regression Risk
Neither starter's ERA is far out of line with his fielding-independent numbers.
- Starter ERA (away) 3.22 MLB Stats API
- Starter FIP (away) 3.15 MLB Stats API
- Starter ERA (home) 3.92 MLB Stats API
- Starter FIP (home) 3.93 MLB Stats API
- Team BABIP (away) Unavailable MLB Stats API
- Team BABIP (home) Unavailable MLB Stats API
Live Game State
The game has not started, so score, inning and base state carry no weight yet.
Data Sources & Freshness
Each supporting statistic above carries its source and latest available update date. Missing feeds are marked unavailable and do not receive model weight.
Estimate generated Sep 26, 2026 3:52 PM.
This is a custom NumSOX estimate based on baseball statistics, not a betting line or a prediction of certainty.
- Starting Pitcher (3.15 FIP)
- Regression Risk (+0.07 ERA-FIP)
- Defense (.708)
- Ballpark Fit (103 runs)
- Historical Calibration (-2 pts)
- Defense (.728)
- Ballpark Fit (114 HR)
- Historical Calibration (+2 pts)
- Starting Pitcher (3.93 FIP)
- Regression Risk (-0.01 ERA-FIP)