Major League Baseball plans to crack down on pitchers using illegal substances to get a better grip on the baseball.

The league has made repeated efforts to dissuade pitchers from doing so.

According to sources, details on the more aggressive enforcement were still being worked out after owners were informed that the practice is prevalent around baseball.

Umpires will be given more latitude, while MLB's current thinking is to also put more responsibility with teams to apply the rules and to better enforce the rules in the minor leagues.