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NRFI (No Run First Inning) wins if neither team scores in the 1st inning. Here is how to read NRFI prices, when the bet has value, and what to check before tailing.
NRFI (No Run First Inning) wins if neither team scores in the 1st inning. YRFI (Yes Run First Inning) is the opposite side. Most sportsbooks list both, sometimes labeled "1st Inning Score: Yes/No." The bet resolves after the bottom of the 1st, usually 8-15 minutes into the game.
NRFI prices range from -160 in elite pitcher matchups down to +105 in big-hitter spots. The most common range is -115 to -140. To convert: -130 = 56.5% implied probability. The league-wide 1st-inning scoreless rate has run about 50-53% in recent seasons, so -130 is a losing price on a random game and only +EV when the matchup pushes well above baseline.
When several of the factors above stack the same way, a matchup's scoreless probability can climb well above the roughly 50-53% league baseline. At -130 (56.5% implied), you need a true probability above 56.5% just to break even. Bookie Bullies has no first-inning odds feed, so its board rates each game by model probability alone: a LOCK or LEAN needs named starters and a 60%+ probability on one side.
For every MLB game, the model computes P(both sides score 0 in 1st) from per-half Poisson rate estimates. Each rate starts from a league first-inning base and is scaled by the opposing starter (season FIP blended toward his first-inning ERA), the park, wind, the home-plate umpire, team defense, and the game's posted total. Lineup strength is logged but not used. Bookie Bullies has no first-inning odds feed, so it does not compare against a price: every game gets a read on the first-inning board, and only reads with named starters and a 60%+ side probability are rated LOCK or LEAN.
NRFI stands for No Run First Inning. The bet wins if neither team scores in the 1st inning of an MLB game. The bet loses if either team plates a single run before the second inning starts. The bet resolves binary, no push.
YRFI stands for Yes Run First Inning. It is the inverse of NRFI. YRFI wins if at least one team scores in the 1st inning, and loses if the inning ends scoreless. NRFI and YRFI cover all outcomes between them at any given game.
Roughly 50-53% of MLB games have ended the 1st inning scoreless in recent seasons. This is the baseline before any matchup adjustments. Sportsbooks price most NRFI lines between -115 and -140, which translates to 53.5% to 58% implied probability, so the typical NRFI price sits above the baseline rate on a random game.
NRFI is profitable long-term only when the bettor identifies matchups that push well above the league-wide baseline. The book's vig means -130 NRFI requires a 56.5%+ hit rate just to break even. Bettors who consistently target high-K, low-walk pitchers in pitcher-friendly parks can clear that bar; bettors who blindly back the favorite NRFI on every game lose to the vig.
The model computes first-inning scoreless probability per game from per-half Poisson rates scaled by the starting pitcher (FIP blended toward his first-inning ERA), park, wind, home-plate umpire, team defense, and the game's posted total. There is no first-inning odds feed, so it does not compare against a price: reads with named starters and a 60%+ side probability are rated LOCK or LEAN, and the public record reports hit rate, not ROI.