Home runs are being hit at their lowest rate in nearly a decade, and the culprit appears to be the ball itself.
By the numbers: Through seven weeks, MLB teams are hitting 0.98 HR per game, down 20% from last year (1.22) and 29% from the all-time high in 2019 (1.39).
State of play: Put simply, fly balls aren't turning into home runs as often as they did in recent seasons.
- From 2017 to 2021, fly balls hit in April and May with an exit velocity of 105–110 mph left the yard 81% of the time, per FiveThirtyEight. This year, that's down to 74%.
- The same is true at lower exit velocities: 100–105 mph (45% down to 34%); 95–100 mph (13% down to 9%).
Between the lines: This year's ball is experiencing more drag, per FanGraphs, and there's no definitive answer as to why — though humidors could be playing a role.
- All 30 ballparks are now storing balls in humidors to standardize the amount of moisture they retain, and one astrophysicist believes that is causing the decreased offensive output.
- "The ball ain't the same as it used to be," Brewers DH Andrew McCutchen told ESPN earlier this month.
The big picture: If this sounds familiar, that's because it is. The composition of the baseball, and how it affects MLB's on-field product, has become a recurring theme over the past eight years.
- Juiced: Home runs shot way up 2015-17, driving rumors of a "juiced" baseball. Studies showed the ball was indeed bouncier and experienced less drag.
- HR barrage: The HR record was shattered in 2019, which MLB said was mostly due to players embracing the launch angle revolution. An independent study disagreed, suggesting balls were being machine-dried, which lowered the seams and reduced drag.
- De-juiced: Rates have fallen for three straight years, and MLB said it was altering balls last season to improve consistency. But a report last winter said MLB used two distinctly different balls in 2021.
The bottom line: For the eighth straight baseball season, a major talking point is the ball — a fundamental piece of equipment that MLB just can't seem to keep consistent.