It was another rough day on Wednesday, going 1-3 including a NRFI where the game's only run was scored in the first inning. Sportsbooks seem to have adapted a bit throughout the season, juicing the "yes" side of this bet a bit heavier in response to all of the value we were finding there. We can adapt too though, and I've also updated all of my databases heading into Thursday to try to right the ship.
The Model
The process is relatively simple. First, I start by assuming that the full-game (implied) run totals for either team are roughly efficient. As mentioned above, that tends to be the case more often than not. This saves me the trouble of trying to predict the total runs scored in the game — and allows me to focus strictly on the "when" rather than "how many."
Next, I built a database of pitchers' performance the first time through the order, relative to their overall stats. Since the latter is presumably baked into the full-game total, I wanted to figure out if those runs are more likely to come early or late. Most — but not all — MLB starters do somewhat better early in games, but with some variance in just how much. The model uses xFIP (expected Fielding Independent Pitching) as the ERA predictor of choice.
That's only half of the equation, though, with the offenses making up the other half. To do this, I looked at what percentage of a team's total runs is produced by the top-three batters in the lineup. While a first inning run scored, by definition, needs at least four hitters to come to the plate, one of the first three has to actually score it. The metric of choice here is wRC+, based on the projected lineup for the day from each team.
This is a bit of a tradeoff, as lineups (and run totals) can shift throughout the day, especially if significant contributors miss time. However, in my experience the inefficiency of the morning lines more than makes up for the leakage in the model. With that said, exercise caution if, say, Mike Trout is listed as questionable for the night's game.
The Picks
With all of the picks below, I'll include the pick, the best line and the threshold I'd bet it to. These will go up in the morning, so if any major news breaks between publishing and when you read it, be sure to consider that.
Infrequently, rather than betting on the traditional YRFI/NRFI, the pick will be on one team or the other specifically to score a run, which as of this writing is only a betting option at DraftKings. Since the model handles each team individually, sometimes one team is projecting for a greater proportion of the "run equity" in the first inning than the betting lines are accounting for.
NRFI Odds, Picks for Thursday, August 10
Minnesota Twins vs. Detroit Tigers NRFI: Two of the least top-heavy lineups in baseball square off, with the Tigers having the added benefit of being bad overall. Twins starter Kenta Maeda also has solid first time through the order splits. There's a bit of a risk on the Twins side, but we just need three outs from Reese Olson to cash this one.
Washington Nationals vs. Philadelphia Phillies NRFI: The Nationals side of this is obvious — they're one of the worst offenses in baseball, taking on an ace in Aaron Nola. However, the Phillies are projecting for less chance of scoring than you might think. As bad as Patrick Corbin has been for years now, he's actually solid early in games. His xFIP the first time through the order is a solid 3.86, making this a strong value at plus-money.
