Every year, Major League Baseball has a slightly different flavor. The ingredients are always the same -- a ball, a bat, a glove, hitting, pitching, catching, etc. The portions in the recipe are ever-changing, but, weather aside, baseball still tastes more or less the same on the last day of the season as it did on Opening Day.
That's how it usually goes, anyway, but not in 2021. Thanks to baseball's unprecedented in-season initiative to crack down on foreign substances being applied to the ball, the flavor of this season has been radically altered. Someone has dumped a mysterious new ingredient into the mix and we know the updated concoction tastes different, but we just can't put our finger on exactly how.
Some hard facts:
MLB Aggregate Spin Rate by Month
April: 2,272 rpm
May: 2,282 rpm
June: 2,223 rpm
July: 2,197 rpm
The new guidelines went into effect in the middle of June, but I present these figures by month to make a point. Since we've tracked spin rate, whatever figures that blend together to create that metric don't tend to fluctuate much within a season. Last year, the aggregate spin rate varied by 11 rpm from the highest monthly figure to the lowest. In 2019, the spread from highest month to lowest month was just 12 rpm. So that 85 rpm difference between May and what we had in July before the All-Star break is immense.
This dramatic on-the-fly change to the way baseball is played during a season is both stark and unclear. It's stark in that we can see how dramatically spin rates have fallen. It's unclear because the impact of that change in terms of on-field results remains difficult to suss out from other factors that affect the flow of season results, the biggest of which is the weather.
Still, two assumptions seem pretty safe. One, the drop in overall spin has had and will have an impact of baseball's level of offense. And, two, that impact will not be uniformly divided among the 30 teams.
With that in mind, let's look at some early winners and losers from the spinning wheel of baseball's declining spin rates.