The Cubs have the advantage based mainly on the live score and game situation, with pregame team strength still playing a smaller role.
Why 60%?
7 of 15 categories could be scored from the data on file. One or both starters are unconfirmed, which lowers confidence. The game is live, so the estimate leans on the actual game state. The 8 unscored categories are listed openly rather than guessed at, and their weight is shared across the categories that could be measured.
Offense
The away club has a strong edge in offense (113 vs 100 wRC+).
- Team wRC+ (away) 113 MLB Stats API
- Team wRC+ (home) 100 MLB Stats API
- Team OPS (away) .765 MLB Stats API
- Team OPS (home) .717 MLB Stats API
- Runs per game (away) 5.24 MLB Stats API
- Runs per game (home) 4.27 MLB Stats API
- Hard-hit % (away) Unavailable MLB Stats API
- Hard-hit % (home) Unavailable MLB Stats API
Starting Pitcher
One or both probable starters have no stat line yet.
Bullpen
Bullpen splits have not been imported for both clubs.
Lineup / Platoon
The away club has a strong edge in platoon matchups (.793 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) .793 MLB Stats API
- OPS vs RHP (away) .756 MLB Stats API
- OPS vs LHP (home) .733 MLB Stats API
- OPS vs RHP (home) .711 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 (.727 vs .708 defensive efficiency). DRS and UZR have no free public source and are left out rather than estimated.
- Defensive efficiency (away) .727 MLB Stats API
- Defensive efficiency (home) .708 MLB Stats API
- Outs Above Average (away) 72 MLB Stats API
- Outs Above Average (home) 19 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 home club has a clear edge in recent form (4-6 vs 5-5 over ten games). Ten games is a small sample, which is why this is weighted lightly.
- Last 10 (away) 4-6 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) L2 MLB Stats API
- Streak (home) W2 MLB Stats API
Ballpark Fit
Fenway Park suppresses home runs (95 home run factor). The away club has a slight edge in how this park suits them (.180 vs .150 ISO).
- Run park factor 104 MLB park-factor baseline (multi-year estimate)
- Home run park factor 95 MLB park-factor baseline (multi-year estimate)
- Double park factor 117 MLB park-factor baseline (multi-year estimate)
- Team ISO (away) .180 MLB Stats API
- Team ISO (home) .150 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 11 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 +11 pts to the Red Sox NumSOX backtest
Regression Risk
Needs ERA and FIP for both starters to compare surface results with fielding-independent ones.
Live Game State
The game is under way, so the score, inning, outs and base state are doing most of the work. MLB's per-play model has the home club at 42%. This is a high-leverage spot, so the number can move sharply.
- Live win probability (home) 42% MLB Stats API
- Live win probability (away) 58% MLB Stats API
- Leverage index 2.34 MLB Stats API
- Plays scored 36 MLB Stats API
- Detailed inning, outs and base state Unavailable
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 27, 2026 4:11 PM.
This is a custom NumSOX estimate based on baseball statistics, not a betting line or a prediction of certainty.
- Offense (113 wRC+)
- Lineup / Platoon (.793 OPS)
- Defense (.727)
- Ballpark Fit (104 runs)
- Live Game State (58%)
- Recent Form (4-6)
- Historical Calibration (-11 pts)
- Recent Form (5-5)
- Historical Calibration (+11 pts)
- Offense (100 wRC+)
- Lineup / Platoon (.733 OPS)
- Defense (.708)
- Ballpark Fit (95 HR)
- Live Game State (42%)
Probable starter has not been announced and there is not enough recent rotation history to predict it responsibly.