An NRFI bet wins if neither team scores a run in the first inning of a baseball game. It is settled once the first inning is over, top and bottom, so the result is known long before the game ends.
The opposite bet is YRFI: at least one run in the first inning, by either team. Over the last two MLB regular seasons the two came out almost exactly even, and that split is the number every NRFI price has to be read against.
What does NRFI mean?
NRFI stands for “no run first inning”, and YRFI for “yes run first inning”. The bet covers both halves of the inning together: the visitors bat in the top, the home team in the bottom, and a single run in either half makes YRFI the winner.
MLB’s Official Baseball Rules define an inning as the part of a game “within which the teams alternate on offense and defense and in which there are three putouts for each team”, and each team’s turn at bat as a half-inning (2026 Official Baseball Rules, Definitions of Terms). So the first inning ends on the sixth out, three for each side.
A first-inning total set at 0.5 runs is the same bet in another form: under 0.5 means no run, over 0.5 means at least one.
How often the first inning ends scoreless
We counted every completed regular-season game in the last two seasons from ESPN’s linescores and checked the first-inning run totals against MLB’s own figures, which matched to the run.
| Season | Games | No run in the 1st | Share | Top of the 1st scoreless | Bottom of the 1st scoreless |
|---|---|---|---|---|---|
| 2025 | 2,430 | 1,210 | 49.8% | 71.9% | 69.0% |
| 2026 | 2,429 | 1,200 | 49.4% | 73.1% | 67.6% |
Across both seasons, 2,410 of 4,859 games had no run in the first inning: 49.6%. YRFI won the rest, by 10 games in 2025 and by 29 in 2026.
The two halves explain the even split. The visitors were held scoreless in the top of the first about seven times in ten, and the home team about two times in three. Multiply the 2025 rates, 71.9% by 69.0%, and you get 49.6%, close to the 49.8% that happened. Each half on its own favors no run; NRFI needs both.
Why the starting pitchers matter
Each half of the first inning begins with a starting pitcher on the mound and the top of a batting order at the plate. So the bet comes down to the first few hitters of each lineup against one pitcher each.
Our view: the two starters are most of what separates one game’s first inning from another’s. The league-wide 49.6% is an average across every pairing of pitchers, not a fair price for any single game.
How an NRFI bet is settled
Books write their own rules, and two of them read on October 16, 2026 show the shape.
- The inning must finish. FanDuel’s house rules (Massachusetts, effective July 30, 2026) say the relevant inning or half inning “must be fully completed for bets to stand”, unless a total runs market is already decided. Circa Sports’ Nevada rules say every segment wager, innings included, “must be completed in full”.
- A rained-out game. FanDuel voids wagers on a game that does not start on its scheduled day, and keeps them if a started game is suspended and resumes within 48 hours.
- A pitcher change. At FanDuel, markets other than the moneyline are “Action” and stay open “regardless of any personnel change”. On that wording, a scratched starter does not void a first-inning bet there. Rules on pitcher changes are each book’s own, so the rule at your own book is the one to read.
What an NRFI price says
A price states a chance: at -110, a bet has to win 52.38% of the time to break even (110 divided by 210). With both NRFI and YRFI at -110, the two chances add to 104.76%, and the extra 4.76 points is the book’s margin. Take the margin out and each side is a 50% call. These prices are an illustration; MLB’s regular season is over, and no first-inning price was read for this page.
Against that, the measured share is 49.6%. Had every NRFI been priced at -110, backing it in every game would have won 49.6% of the time across the two seasons, short of the 52.38% that price needs. So the average says little about any one game, where the two starters move the chance away from it. Our guide to how betting odds work shows the conversion for any price.
NRFI sits with the other bets on something inside the game; our prop betting guide covers the family. For the starter’s own line, our guide to pitcher outs props explains how outs recorded are counted, and the MLB predictions page carries our game calls when the season is on.