The Red Sox have a strong edge because their starting pitching, defense and recent form are stronger overall.
Why 62%?
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 101 wRC+).
- Team wRC+ (away) 100 MLB Stats API
- Team wRC+ (home) 101 MLB Stats API
- Team OPS (away) .717 MLB Stats API
- Team OPS (home) .722 MLB Stats API
- Runs per game (away) 4.27 MLB Stats API
- Runs per game (home) 4.36 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 (3.50 vs 4.00 FIP).
- Starter FIP (away) 3.50 MLB Stats API
- Starter FIP (home) 4.00 MLB Stats API
- K-BB% (away) 15.4 MLB Stats API
- K-BB% (home) 14.2 MLB Stats API
- WHIP (away) 1.10 MLB Stats API
- WHIP (home) 1.52 MLB Stats API
- Opponent OPS (away) .655 MLB Stats API
- Opponent OPS (home) .781 MLB Stats API
Bullpen
Bullpen splits have not been imported for both clubs.
Lineup / Platoon
The away club has a slight edge in platoon matchups (.733 vs .723 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) .723 MLB Stats API
- OPS vs RHP (home) .723 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 away club has a strong edge in defense (.708 vs .688 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) .688 MLB Stats API
- Outs Above Average (away) 20 MLB Stats API
- Outs Above Average (home) -35 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
The away club has a clear edge in recent form (5-5 vs 3-7 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) 3-7 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
Sutter Health Park plays big for power (108 home run factor). The home club has a slight edge in how this park suits them (.150 vs .160 ISO).
- Run park factor 105 MLB park-factor baseline (multi-year estimate)
- Home run park factor 108 MLB park-factor baseline (multi-year estimate)
- Double park factor 102 MLB park-factor baseline (multi-year estimate)
- Team ISO (away) .150 MLB Stats API
- Team ISO (home) .160 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 4 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 -4 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) 3.65 MLB Stats API
- Starter FIP (away) 3.50 MLB Stats API
- Starter ERA (home) 5.47 MLB Stats API
- Starter FIP (home) 4.00 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 5:23 PM.
This is a custom NumSOX estimate based on baseball statistics, not a betting line or a prediction of certainty.
- Starting Pitcher (3.50 FIP)
- Lineup / Platoon (.733 OPS)
- Defense (.708)
- Recent Form (5-5)
- Historical Calibration (-4 pts)
- Regression Risk (+0.15 ERA-FIP)
- Historical Calibration (+4 pts)
- Regression Risk (+1.47 ERA-FIP)
- Starting Pitcher (4.00 FIP)
- Lineup / Platoon (.723 OPS)
- Defense (.688)
- Recent Form (3-7)