After taking apart and examining twenty-six baseballs, a possible explanation for the rise in both home runs and pitcher blisters emerged: The laces in the newer baseballs are noticeably different.
How one tiny change to the baseball may have led to both the home run surge and the rise in pitcher blisters
How has the baseball evolved over two centuries? Moderately, but notably enough to change outcomes.
Following numerous studies, an MLB commission has confirmed that the baseball has changed since mid-2015.