ESPN published an interesting story on its website at the outset of the baseball season, in which it discussed the new baseballs that were being introduced for the 2021 season and the impact they might have on offense, and in turn, run totals. Its contents, and what we’ve been able to uncover, might be of interest to MLB bettors.
It was pointed out that something similar had been done in the Korean KBO (remember when everybody was watching that during the pandemic?) before the 2019 season, and it reduced the amount of runs per game from 11.1 to 9.1, which, to put it mildly, is a rather precipitous drop.
The new balls weigh less and are, according to the story, “less bouncy.” The seams are also stitched on a little differently, as Blake Snell, the Cy Young winner who went from Tampa Bay to San Diego, remarked that he got a firmer grip on the ball and found it easier to throw breaking balls like curves and sliders.
Okay, so what is the verdict? Well, after only a month of the season it’s probably a little too early to come up with something definitive; after all, run totals and homers will usually experience a small increase in the summer months of June, July and August.
And of course, making comparisons between this season and last won’t provide the ultimate answer either, because of the strange circumstances under which the 2020 campaign was played.
However, it DOES look like offense is trending downward, even taking those factors into consideration.
Thus far, and based on numbers we have compiled from information available at Baseball Reference, 8.6 runs per game are being scored this season, down from 9.3 last year AND 9.66 in 2019.
There is also a considerable reduction with regard to home runs per nine innings, base hits and extra base hits per team per game, and slugging percentage.
Let’s illustrate the way these statistics have trended over a five-year period. Take special note of the way these numbers have dropped over a three-year stretch (including this year):
Runs Per Game
2017 — 9.3
2018 — 8.9
2019 — 9.66
2020 — 9.3
2021 — 8.6
Home Runs Per Nine Innings
2017 — 2.6
2018 — 2.4
2019 — 2.8
2020 — 2.6
2021 — 2.4
Hits Per Game, Per Team
2017 — 8.69
2018 — 8.43
2019 — 8.65
2020 — 8.04
2021 — 7.67
Extra-Base Hits Per Game, Per Team
2017 — 3.15
2018 — 3.02
2019 — 3.31
2020 — 2.99
2021 — 2.75
Slugging Percentage
2017 — .426
2018 — .409
2019 — .435
2020 — .418
2021 — .390
As you might be able to see, we are seeing a low for each of these numbers for the five-year period. There could be a number of contributing factors aside from new baseballs.
One is that we have played games almost exclusively in April. So as we’ve mentioned, it’s early and it’s colder. But MLB analytics have dictated different offensive strategies on the part of teams.
Hitters are swinging hard and swinging upward. It is supposed to produce more fly balls and more home runs. Well, not so far. But they’ve been striking out like crazy.
Strikeouts Per Nine Innings
2017 — 16.6
2018 — 17.0
2019 — 17.8
2020 — 18.2
2021 — 18.6
So since 2017, there has been two less base hits and two more strikeouts per game.That’s a big shift.
Oddsmakers have generally done a pretty good job dealing with this. So far in the 2021 season, 51.3% of all games have gone under the total. But that’s not far out of line with the trends in recent seasons:
Percentage of Games Under the Total
2017 — 50.9%
2018 — 51.5%
2019 — 50.4%
2020 — 51.0%
2021 — 51.3%
Through Saturday’s games, here are the teams that are trending OVER the total (this according to the TeamRankings website):
Cincinnati 18-7-1 (72%)
Atlanta 17-9-1 (65.4%)
L.A. Angels 15-10 (60%)
Minnesota 14-10-1 (58.3%)
Arizona, Philadelphia, Seattle 15-12-1 (55.6%)
And here are the teams that are playing games UNDER the total (listed as over-under-push).
N.Y. Mets 7-12-2 (63.2%)
N.Y. Yankees 10-17 (63%)
Detroit 10-17-1 (63%)
Toronto 9-15-1 (62.5%)
Washington 8-13-2 (61.9%)
Baltimore 10-16-1 (61.5%)
We’ll “bounce” back to this subject relatively soon.
