MLB to test mound distance, 'double-hook' DH in Atlantic League

Major League Baseball purists who reject rule modifications such as doubleheaders featuring seven-inning games and a runner starting at second base during extra-inning encounters may soon hate two new changes.

As Jesse Rogers explained for ESPN, MLB will work with the independent Atlantic League to test both moving the pitching mound rubber back one foot to 61 feet, 6 inches, and also the so-called "double-hook" designated hitter. 

Increasing the distance from the rubber to home plate gives batters extra time to see the ball and, theoretically, will lead to a decrease in strikeout rates that have increased across 15 straight years. That rule change is scheduled to take effect on Aug. 3. 

The "double-hook," however, is for the entire season that starts May 27. It eliminates a team's DH as soon as it removes its starting pitcher from a game. From there, either a relief pitcher or a pinch hitter would bat in place of the DH for the remainder of the contest. This is meant to encourage managers to rely on starters into the later innings of matchups, while also injecting a new element of strategy. 

Logic suggests it's only a matter of time before MLB embraces a universal DH, which will open roster spots and opportunities for MLB Players Association members. All American League clubs already use full-time DHs, and it's unknown if that league would willingly abandon the system and embrace the "double-hook" rule.