Closer look at MLB’s early run of Unders
The story of MLB’s season thus far begins and ends with the lack of offense. There are multiple theories as to why that probably all contributes to the incredible run of fullgame Unders to begin the season.
If you bet $100 on every closing line Under this season in the majors, you’d be +16% ROI and up $3,800 in three weeks of baseball, according to our BetLabs system.
This trend doesn’t quite hold up for the entire game, though. Runs aren’t really down in the first five innings because if you blindly bet the first-five-inning Unders, you would actually be down money this season. You’d have a -3.8% ROI betting the first half Unders each game this season. Scoring has just totally died after the fifth inning as teams have struggled to hit bullpens of any kind.
There have been 237 games played through Sunday in this young MLB season and the run distributions have skewed more heavily toward the early innings than ever.
Average runs per inning in MLB this season: 1st: 1.08; 2nd: 1.01; 3rd: 0.87; 4th: 0.89; 5th: 0.89; 6th: 0.82; 7th: 0.92; 8th: 0.92; 9th: 0.60
There’s a lot of confounding variables that all point in the same direction — against the run-scoring environment — but it’s hard to quantify exactly how much each one is impacting the game. When you also consider the big unknown about the design and flight of the baseballs this season — that MLB seems to change every year without warning — it’s hard to say anything definitively.
What we do know is that pitcher velocity in April is as high as it has ever been. The average four-seam fastball velocity thus far in 2022 is 93.7 mph, which is tied with last season for the highest in MLB history. Usually, pitch speed doesn’t peak until the summer, so the fact the record is already tied in the colder April months is stunning.
One reason for that is the expanded rosters. Teams have 28 players on their rosters to start the season and with the expanded DH, that means teams went shorter on their benches and deeper in the bullpens. The extra pitchers mean that fewer and fewer starters are going through the order a third time, unless it’s one of the best pitchers in the league.
The advantage typically goes to the batter in innings 4-6 as the starter wears down, but since teams are going to the bullpen, a fresh flamethrower is coming in and shutting down scoring.
Many have pointed to the deadened ball that MLB was supposed to introduce last season but has committed to fully bringing in for the 2022 season. We don’t have enough batted balls to make any definitive conclusions, but the home-run rate is down from last season and very down from the juiced-ball season of 2019. Others have pointed to humidors being installed in all ballparks this season as a source of the decline in scoring.
It also could be the shortened spring training hurting the hitters’ chances of really getting their timing down because of limited reps in March. With all of these factors, the market has clearly taken a few weeks to adjust to the dip in scoring, but totals over the past few days suggest that the run environment has been lowered considerably by bookmakers.
There were 141 games played between Opening Day on April 7 and April 17. The average closing total of these games was 8.79 runs. Books started to bring totals down by the end of that period, and from April 21-24, the average total was just 8.01 runs. Even despite the clear drop, Unders finished 12-2 on Friday night.
The potential causes of the scoring decrease are endless: The expanded rosters and bullpens, the uptick in pitching velocity, the shortened spring training affecting hitters’ timing, the humidors and new baseballs lowering the home-run rate as balls die at the track.
All of these confounding variables make it hard to predict, but for me, the most fascinating statistic is the fullgame vs. first five-innings difference. Run scoring has completely died after the starters have left games this year and I don’t know how long it’s going to be until that changes with relievers throwing this hard in April in cold weather. Home-run rates will eventually increase with the summer months, but velocity could, too.
Takeaway: I’m going to keep looking for live Unders in games that start with a lot of offense, once the starters are removed.