15 Obscure Baseball Rules You Probably Don't Know (Hat Catches, Balks, and More)

The Rule: If a fielder intentionally uses any piece of equipment — a cap, helmet, mask, or glove that has been thrown — to catch or stop a fair or foul ball, the ball is dead and the batter and all runners are awarded three bases (or two bases if the ball was a fair ball that the fielder intended to catch but deflected off his body first).

Official Rule: MLB Rule 5.06(b)(4)(C) — formerly Rule 7.05(c)

The Catch: Yes, the player can be ejected if the umpire determines it was a deliberate attempt to deceive. More commonly, the penalty is just the base award — but if a player throws their glove at a ball to stop it, expect a quick ejection and possibly a suspension.

Real Example: In 2012, Minnesota Twins outfielder Josh Willingham accidentally trapped a ball against his body and then secured it with his bare hand near his cap. The umpires had a long discussion about whether the cap had been "used" — it hadn't, but the play shows how sensitive this rule is.

Why it matters in youth baseball: Kids will sometimes instinctively trap a ball with their body or cap. Umpires at the travel ball level will enforce this rule, and giving up three bases can change a game.

The Rule: A balk is any illegal motion by the pitcher with one or more runners on base. The penalty: all runners advance one base. There are 13 specific balk situations in the MLB rulebook.

Official Rule: MLB Rule 6.02(a)

Common balks:

• Not coming to a complete stop in the set position
• Starting the pitching motion and then stopping
• Faking a throw to first base without stepping off the rubber
• Dropping the ball while on the rubber
• Not stepping directly toward a base before throwing there
• Turning the shoulders after coming set

Real Example: In 2023, MLB umpires called 328 balks across the entire season. The most common: not coming to a "discernible" complete stop. Umpires are trained to watch for even a micro-hesitation that's too quick.

Youth baseball note: In USSSA and USA Baseball tournaments, balk rules are often modified for younger age groups. In 9U-10U, umpires may give a warning on the first balk instead of awarding bases. By 12U, full enforcement is standard.

The Rule: A batter is out if they hit a fair ball a second time with their bat while in the batter's box. However, if the bat accidentally strikes the ball a second time after the batter has left the box and the bat is in the air, the ball is live and in play.

Official Rule: MLB Rule 5.09(a)(8)

The nuance: If a batter hits a ball that bounces back up and hits the bat again while the batter is still in the box, they're out. But if the batter drops the bat and the ball rolls into it, the ball is live — no penalty.

Real Example: In 2019, Pittsburgh Pirates batter Adam Frazier hit a ball that bounced off the ground and back into his bat while he was still in the box. He was called out. But if he'd taken one step out, it would have been a live ball.

Parent tip: Tell your kid — after you hit the ball, drop the bat and run. Don't stand there and let the ball come back and hit your bat.

The Rule: With runners on first and second (or bases loaded) and fewer than two outs, if a fair fly ball — other than a line drive or bunt — can be caught by an infielder with ordinary effort, the batter is automatically out. Runners may advance at their own risk.

Official Rule: MLB Rule 5.05(a)(5)

Why it exists: Without this rule, an infielder could intentionally drop a pop-up and turn a double or triple play, since the runners can't advance on a dropped ball (because the batter is forced out at first only if the ball is caught — confusing, right?). The rule protects the runners.

The controversy: In the 2012 NL Wild Card Game, the Atlanta Braves' Andrelton Simmons hit a pop-up to left field. The Cardinals' shortstop drifted out and called it, then backed off. Left fielder Pete Kozma also called it. The umpire called "infield fly" — even though the ball was 200 feet into the outfield. Fans went ballistic. The rule says "can be caught by an infielder with ordinary effort" — and Kozma was an infielder. The call stood.

Youth baseball: Infield fly is called at most 12U and above travel ball tournaments. It is almost never called in 8U-10U rec ball. Teach your runners to "tag up" (retouch their base) when the umpire calls it, because the batter is already out.

The Rule: If the catcher (or any fielder) hinders the batter's swing, the ball is dead, the batter is awarded first base, and any runner forced to advance moves up a base.

Official Rule: MLB Rule 5.06(b)(3)

What it looks like: The batter's bat makes contact with the catcher's glove during the swing. The batter gets first base even if they would have gotten a hit.

The twist: If the batter still hits the ball fair despite the interference, the offensive manager can choose — take the result of the play OR take the interference award (batter to first, forced runners advance).

Real Example: In Game 6 of the 2019 World Series, Anthony Rendon was awarded first base on catcher's interference. It loaded the bases for the Washington Nationals, who went on to win the game and the series. Catcher's interference can change history.

Youth baseball: Very common at 9U-12U. Catchers are still learning positioning. If your kid keeps hitting the catcher's glove, ask the coach to move the catcher back — but also check your kid's stance; they might be standing too close to the plate.

The Rule: If a spectator reaches out of the stands and touches a live ball, the ball is dead. The umpire awards the batter and runners the bases they would have reached, in the umpire's judgment, had there been no interference.

Official Rule: MLB Rule 3.16 and Rule 5.05(b)(6)

Real Example: The most famous case is the 2003 "Steve Bartman incident" at Wrigley Field. The Cubs were five outs from the World Series. Luis Castillo hit a foul ball near the left-field wall. Bartman reached for it, and Moises Alou couldn't make the catch. The Cubs fell apart and lost the game and the series. Bartman received death threats and had to go into hiding. It took a 2016 World Series win for Cubs fans to begin forgiving him.

Another famous case: In 1996, 12-year-old Jeffrey Maier reached over the right-field wall at Yankee Stadium and pulled Derek Jeter's fly ball into the stands. The umpire called it a home run. The Orioles protested — the ball was clearly reachable by right fielder Tony Tarasco — but the call stood. The Yankees won the game and eventually the World Series.

Youth baseball: In travel ball, if a parent or sibling reaches onto the field and touches a live ball, the umpire will call fan interference and award bases. Keep your hands off the ball unless it's clearly in the stands.

The Rule: The hidden ball trick is completely legal — if done correctly. A fielder hides the ball on the runner, waits for the runner to step off the base, then tags him out.

Official Rule: No specific rule governs it, but MLB Rule 5.06(c) requires the pitcher to be on the rubber with the ball before any pitch. If the pitcher has the ball on the rubber and fakes a throw, that's a balk. But if the pitcher is not on the rubber and the second baseman has the ball hidden, the trick is legal.

The setup: After a pickoff throw to second, the shortstop pretends to throw the ball back to the pitcher but actually keeps it. The runner steps off the base to lead. The shortstop tags him. Out.

Real Example: In 2022, the Houston Astros successfully pulled the hidden ball trick three times in one season. MLB players — professionals who practice every day — still fall for it.

Coaching tip: Teach your pitchers to always have the ball on the mound before a pitch. If the umpire calls time and you don't have the ball, look around — someone might be hiding it.

The Rule: A pitcher shall not bring their pitching hand in contact with their mouth or lips while on the pitching mound (the dirt area). The penalty is a called ball.

Official Rule: MLB Rule 6.02(c)(7)

Why it exists: Pitchers used to lick their fingers to get a better grip on the ball. But saliva is a foreign substance — and after the 1920 Black Sox scandal and later spitball controversies, the league cracked down. Today, with the pitch-tack crackdown of 2021, this rule is enforced more strictly than ever.

The exception: When the weather is cold (below 50°F), the umpire can permit pitchers to blow on their hands — but only if both managers agree before the game.

Youth baseball: USSSA and USA Baseball follow this rule. If your kid licks their fingers on the mound, the umpire will call a ball. Tell them to wipe their hand on their pants instead.

The Rule: If a runner runs the bases in reverse order to confuse the fielders or to make a mockery of the game, the runner is out. The ball is dead.

Official Rule: MLB Rule 5.09(b)(10)

Real Example: In 1908, Germany Schaefer of the Detroit Tigers literally ran from second base back to first base to confuse the catcher and allow a runner on third to steal home. The umpire had no rule to stop him, so the play stood. The rule was added afterward specifically because of him. Schaefer is the reason this rule exists.

The line: Running the bases in reverse to make a play is illegal. Running in reverse to retouch a missed base (e.g., you skipped second base) is perfectly legal and happens all the time.

Youth baseball: You won't see this often, but if a kid starts running backward to be funny, the umpire will call them out and may eject them for making a mockery of the game.

The Rule: A batter-runner running to first base must stay within the three-foot lane (the last half of the distance to first base) marked on the field. If they're outside the lane and interfere with the fielder taking the throw at first, they're out.

Official Rule: MLB Rule 5.09(a)(11)

The nuance: The batter-runner is allowed to step outside the lane to avoid a thrown ball that would hit them. But they can't step out to interfere with the first baseman's catch.

Real Example: In 2015, the Minnesota Twins' Danny Santana was called out for running outside the three-foot lane and interfering with the first baseman's ability to catch the throw. The call was upheld on review.

Youth baseball: Most travel ball fields have the three-foot lane painted. Teach your kids to run inside the lane — especially on ground balls to the right side where the first baseman is stretching toward the bag.

The Rule: Once a pinch-hitter is announced (or enters the game), the original batter is out of the game. But here's the twist: if the opposing team changes pitchers after the pinch-hitter is announced but before the first pitch, the offensive manager can send up a different pinch-hitter. The originally-announced pinch-hitter is then out of the game without ever batting.

Official Rule: MLB Rule 5.10(b)(2)

Why it matters: This is a chess-move strategy. Manager A sends up a right-handed pinch-hitter. Manager B counters with a left-handed reliever. Manager A pulls the righty and sends up a lefty. Manager B just burned a reliever for nothing.

Real Example: In a 2023 game between the Dodgers and Padres, Dave Roberts pulled this exact move. The Padres burned two relievers in one at-bat. The pinch-hitter who replaced the pinch-hitter hit a double.

Youth baseball: This rarely applies at the youth level, but in 13U+ travel tournaments with lineup cards, it can come into play — especially in showcase events with deeper benches.

The Rule: A "foul tip" is a batted ball that goes sharp and direct from the bat to the catcher's hand or glove and is legally caught. It is not a foul ball — it is a live ball, treated as a strike. If it's strike three, the batter is out. Runners can steal on a foul tip.

Official Rule: MLB Rule 5.05(a)(2) and Definition of Terms

The confusion: Most fans hear "foul tip" and think the ball is dead. It's not. If the catcher catches it cleanly, the ball is live. Runners can advance. The only difference from a regular strike is that it's caught by the catcher directly from the bat.

If the catcher drops it: It becomes a foul ball (dead ball, runners return). The distinction is whether the ball was "caught" by the catcher.

Real Example: In a 2021 playoff game, a runner on first base stole second on a foul tip that the batter thought was a foul ball. The batter stopped running, and the runner was safe at second. The batter was called out on strikes. The offensive manager argued, but the call was correct — a foul tip is a live ball.

Youth baseball: This is a crucial rule for 11U+ travel ball. Teach your catchers to catch foul tips cleanly — if they do, runners can't advance and the batter is out on strike three. If they drop it, it's just a foul ball.

The Rule: From the set position, if the pitcher steps toward first base, they must throw to first base. If they step toward first but don't throw, it's a balk. The pitcher cannot fake a throw to first base from the rubber.

Official Rule: MLB Rule 6.02(a)(4)

The exception: The pitcher can fake to second or third base (step off and throw or step toward and fake). But first base — no faking from the rubber.

The workaround: The pitcher can step off the rubber (backward) and then fake a throw to first. Once off the rubber, the pitcher is just a regular fielder and can do whatever they want.

Real Example: Left-handed pitchers are especially dangerous on pickoffs to first because they're already facing first base. Andy Pettitte was famous for his move — he'd come set, look at the runner, and snap a throw to first. But if he came set, turned toward first, and didn't throw — balk.

Youth baseball: This is the #1 balk called in 11U-14U travel ball. Left-handed pitchers love to "look" at the runner and then throw home. If their front foot crosses their back foot toward first, it's a balk — even if they throw home.

The Rule: If a fair batted ball touches a runner before it passes a fielder (other than the pitcher), the runner is out, the ball is dead, and the batter is awarded first base. If the ball has already passed an infielder, the ball is live and the runner is safe (unless another fielder has a play on the ball).

Official Rule: MLB Rule 5.09(b)(3)

The logic: The runner can't interfere with a batted ball that a fielder hasn't had a chance to field. Once the ball is past a fielder, the runner is just unlucky.

Real Example: In 2023, the Astros' Yordan Alvarez hit a rocket up the middle that hit second base umpire — wait, that's different. But in a 2019 game, a Reds runner was called out when he was hit by a batted ball that hadn't passed the shortstop. The batter got first base. The runner was livid — but the rule was clear.

The standing-on-base exception: If a runner is standing on a base and is hit by a batted ball, they are not out — unless the base is in fair territory and the ball hasn't passed a fielder. Wait, actually — if the runner is in contact with the base and is hit by a fair ball that hasn't passed a fielder, they are out. The base doesn't protect you.

Youth baseball: This happens ALL the time in 8U-12U. A kid hits a grounder that hits the runner on second. The umpire calls the runner out, the batter goes to first. Parents go crazy. But the rule is clear: get off the base path when the ball is hit.

The Rule: A designated hitter (DH) bats in place of the pitcher in the batting order. In MLB, the DH is now universal (both leagues) as of 2022. The DH does not play a defensive position.

Official Rule: MLB Rule 5.11

The Ohtani Exception: In 2023, MLB added a special rule: if a player is the starting pitcher and the starting DH, and is removed from the game as a pitcher, they can remain in the game as the DH. This is the "Ohtani Rule," created specifically for Shohei Ohtani, who is both an elite pitcher and an elite hitter.

Before the universal DH: In the American League, the DH was used since 1973. The National League did not use the DH until 2020 (COVID season) and then made it permanent in 2022. For 49 years, NL pitchers hit.

Youth baseball: DH rules vary by tournament. USSSA typically allows a DH for any position player (not just the pitcher). USA Baseball follows similar rules. In high school baseball, the DH can hit for any defensive player, not just the pitcher. Check your tournament's specific rules before the game.