March 23, 2017

Rule of the Week: Switch-Pitchers

Rule of the Week: Switch-Pitchers

You probably know at least one left-handed person. One out of every ten people is left-handed…and only 1% of the population is truly ambidextrous.

In the Major Leagues, however, the numbers are a little different: off the top of your head, you can probably name several leftys easily. After all, more than 25% of the Major Leagues is left-handed. But what about those players who can throw or bat with both arms?

While switch-hitters are fairly common in the Major Leagues, switch-pitchers are extremely rare.

Famous Switch-Pitchers

In the 20th century, only four pitchers were known to switch-pitch: Tony Mullane, Elton P. “Ice Box” Chamberlain, Larry Corcoran, and George Wheeler.

In the last century, we’ve seen far fewer switch-pitchers in the Major Leagues. Greg Harris broke records in 1995 playing for the Montreal Expos when he pitched with both arms against the Cincinnati Reds, ending the inning and earning a standing ovation from the crowd.


Advantages of left-handedness

There have been lots of arguments for playing baseball left-handed in the Majors. Aircraft engineer and Washington University professor David Peters makes an argument for how baseball is “rigged for lefties”, claiming that everything from ballpark design to baseline angles to gaining momentum on the plate all favors the left-handed. That’s why left-handed pitchers are so sought after in MLB.

When is a pitcher allowed to switch arms?

It makes sense, then, for pitchers to want to pitch left-handed. But how many ballplayers can actually throw strikes with both arms? Though rare, MLB has a rule for that.

Many of you will have taken notice of Pat Venditte, the highly skilled switch-pitcher on the Seattle Mariners roster. (Though he is not fully ambidextrous off the mound, he does use both arms regularly in pitching.) In 2008, Venditte, then playing in the minors, and switch-hitter Ralph Henriquez took almost ten minutes switching sides, drawing attention to an unusual situation.

The long and unusual play which inspired the rule:

Venditte’s case is so unusual it forced MLB to create a new rule to specifically address his situation. Also known as the “Pat Venditte Rule,” OBR 5.07(f) requires an ambidextrous pitcher to choose a side before the batter steps to the plate.

The rule also requires the pitcher to “indicate visually” which arm he is going to pitch with. Once he has decided, he cannot switch arms until the next batter is up – and he doesn’t get any warmup pitches. There is a loophole provision with this one, too: if the pitcher gets injured and needs to use the other arm, he may not return to the injured arm for the rest of the game.

If baseball is “rigged for lefties,” it is certainly not rigged for the ambidextrous pitchers. In fact, this rule favors the batter!

Watch baseball rules expert Rich Marazzi’s take on rule 5.07(f): Ambidextrous Pitchers

The same rule holds true even at the Little League level, where more players are likely to be ambidextrous. Little League Rule 8.01(f) states that the pitcher must show the umpire, batter, and runners which arm he/she will throw with, and the pitcher cannot switch arms during that at-bat, and gets no extra prep or warmup time. And if the pitcher becomes injured during that at-bat, just like in OBR 5.07(f), the pitcher may switch arms but is not permitted to throw with the injured arm again for the remainder of the game.

In high school baseball, the rules are clear about how many pitches an ambidextrous pitcher can throw. According to NFHS 6-1-6, “an ambidextrous pitcher is considered one pitcher.” That means any pitch he throws, from any arm, counts toward the total pitch count. The rulebook advises umpires to make sure they know the specific number of pitches for their particular state.

When can a switch-hitter switch sides at the plate?

Look for this topic in our next Rule of the Week.

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Official Baseball Rule 5.07(f): Ambidextrous Pitchers


High School Rule 6-1-6

Little League Rule 8.01

Sources and for more reading:

Don't strike out!

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