Direct Answer
MLB is driven by the moneyline and run line. Starting pitchers, parks, and umpires materially affect prices.
Overview
Baseball is a moneyline market because run differentials are too compressed for traditional spreads. Run lines are fixed at 1.5 runs. Park factors, starting pitcher matchups, and umpire strike-zone tendencies are the foundational inputs.
Bet types
Moneyline
Outright winner. Most common MLB wager type.
Run Line
Fixed 1.5-run spread. The favorite must win by 2 or more; the underdog can lose by 1 or win outright.
Total
Combined runs. Park factor, weather, and bullpen quality are central.
First Five Innings
Wagering on the first five innings only, sidestepping bullpen variance.
Player Props
Strikeouts, hits, total bases, and home run props are the most active markets.
Key concepts
Starting Pitcher Quality
Projected ERA, expected strikeout rate, and recent form are the largest single moneyline inputs.
Park Factor
Stadiums systematically inflate or suppress run scoring. Coors Field and Fenway play differently from Petco or Oakland.
Bullpen Fatigue
Late-inning leverage often shifts to relievers; back-to-back high-leverage outings degrade performance.
Umpire Tendencies
Strike zone size varies measurably by umpire and affects totals and pitcher props.
Common mistakes
- Backing heavy moneyline favorites without considering the run line value.
- Ignoring weather, especially wind direction at outdoor parks.
- Treating bullpen blowups as random when leverage history is predictive.
Frequently asked questions
Is the run line a better bet than the moneyline?+
It depends on the matchup. The run line offers better odds on favorites but adds the risk of a one-run loss, which is the modal MLB game margin.