After attempting to exploit the loophole, New York Mets starting pitcher Max Scherzer was called for a balk on a quick pitch. Rich Storry-USA TODAY Sports

Major League Baseball is pulling a “not so fast” on opportunistic pitchers.

Mark Feinsand of MLB.com reported on Saturday that the league sent a memo to teams clarifying that umpires will call a “quick pitch” violation if the pitcher delivers the ball before the batter is “reasonably set” in the box. Feinsand notes that the penalty for a quick pitch is an automatic ball if the bases are empty or a balk if there are runners on.

The news comes after several pitchers had already tested the limits of the pitch clock rules in spring training, including New York Mets veteran Max Scherzer. During a spring game this week against the Washington Nationals, Scherzer remained set to throw after Nationals batter Riley Adams called for time. Then the instant that Adams was ready again, Scherzer fired away, resulting in a swinging strike-three.

For their part, batters are required to be “in the box and alert to the pitcher” by the eight-second mark of the pitch clock or else they will get a penalty of their own (an automatic strike). That push-and-pull has led to a major feel-out process this spring (during which we have already seen some lightning-fast at-bats as well).

Feinsand notes that the quick pitch rule has always been in place to protect player safety. But not many knew how the newly implemented pitch clock would affect that rule, if at all. Now we have our answer.

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