Major League Baseball will suspend pitchers 10 days if they are caught using "any foreign substance," according to ESPN's Jeff Passan.
MLB is expected to distribute a memo to teams detailing its new policy on Tuesday, per Passan. Widely-used substances such as sunscreen will now be banned, as will Spider Tack, a now-popular grip substance.
The use of different substances to affect a baseball's movement is a decades-long practice, though it has come under greater scrutiny in recent months. More advanced grip enhancers such as Spider Tack have led to a spike in spin rate on various pitches, helping contribute to the league-wide offense shortage.