We turned a slight profit on Thursday, which could've been a much bigger day if we had landed on the correct team-only line. Let's try that one more time on Friday, with a juicy specific-team bet and a few full game lines.
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 Friday, September 22
Tampa Bay Rays vs. Toronto Blue Jays NRFI (-142): While this game has two solid lineups, the 7.5-run implied total is a strong clue that the pitching is likely to rule the day here. Both starters have solid first time through the order splits, making this a fairly easy call at -120.
New York Mets vs. Philadelphia Phillies YRFI (-122): These teams cashed for us yesterday, and we're going back to the well. Both lineups have been fairly top heavy over the last month or two, and the game has a nine-run total. Unlike yesterday, the odds of scoring are fairly even between both teams, so I wouldn't get greedy picking on either one individually.
Cleveland Guardians vs. Baltimore Orioles NRFI (-120): I love this one by the numbers, with the caveat that Shane Bieber is returning from the 60-day injured list for the Guardians. He's been dominant early in games when healthy this season, though I'd understand a fade based on the uncertainty of his form.
Seattle Mariners Team-Specific YRFI (+200): This is another game with a similar expected value between the team-specific and full game line. I like the plus-money odds of the Mariners specifically, though, as they're taking on Dane Dunning, who has a 4.47 ERA as a starter his first time through the order.
