After reading Sandy’s great Brain Game last week about the MLB rule governing what happens if a player catches a ball with his hat or mask or throws his glove at a ball (the batter is awarded three bases and all runners score), we’ve been inspired to go digging for some other strange sports rules. Here are a few other obscure rules you might not have known existed:

1. The Fair Catch Kick

It’s tough to watch a football game without seeing a fair catch, a play where the player returning the opposing team’s punt or kick foregoes his opportunity to run back the ball in exchange for not being touched while trying to catch it. Usually, the receiving team then sends its offense onto the field to start a drive. They don’t have to, though. If the receiving team asks for a fair catch kick, they can use the next play to attempt a free kick. These fair catch kicks are field goal attempts, but they’re undefended. Rather than lining up on the line of scrimmage, the defense has to stand 10 yards downfield, and instead of having a long snapper fire the ball back to the holder, the holder simply starts the play holding the ball for the kicker.

Why would any team try for an uncontested field goal? Usually fair catch kicks only come at the ends of halves; if a team makes a fair catch with 0:00 showing on the clock, its captains can request a free kick, which gives them a chance (albeit a very slight one) to pick up a few points.

Still, it’s fairly uncommon for a half to end with a punt or kickoff. Only a handful of fair catch kicks have been attempted in NFL history, and the last successful attempt came off the toe of Bears kick Mac Percival in 1968. Packers kicker Mason Crosby tried one at the end of the first half of a game against the Lions last season, but the 69-yard boot didn’t quite make it.

2. Substitute Baserunners

Here’s one from MLB’s rules that came into play a few years ago. In 2005, Red Sox infielder Tony Graffanino belted a homer with outfielder Gabe Kapler standing on first base. As the players did their home run trots, Kapler blew out his Achilles tendon rounding second base. Graffanino had to freeze a few paces behind his injured teammate; if he’d passed the downed man, the homer wouldn’t have counted. Eventually, the umps determined that the Sox were entitled to substitute a baserunner for Kapler since he was already entitled to make the full run home.

3. Nailing the Umps

According to MLB’s rule 5.09(g), if a pitched ball lodges in the umpire’s or catcher’s mask or paraphernalia and remains out of play, all runners advance one base.

4. Taking a Plunk While Stealing Home

Jacoby Ellsbury of the Red Sox stole home against the Yankees on Sunday in a thrilling play. What had happened if the pitch from the Yankees’ Andy Pettitte had bonked Ellsbury on the noggin as he tried to slide home, though? According to rule 5.09(h), if any legal pitch touches a runner who’s trying to score, all runners advance. Thus, the other Sox on base would have all moved up a spot as Jacoby looked for an ice pack.

5. Block that Free Throw

There’s a reason they’re called “free” throws. If a basketball player goaltends or attempts to block a freebie, he’s probably a jerk, and he’s definitely getting tagged with a technical foul. Goaltending a free throw is good for a T, but it can also be a strategic weapon. During a 2008 game against Georgia, much-reviled former Kentucky coach was staring at a 3-point deficit with only a few ticks left on the clock at the end of a game. A Georgia player was about to shoot his second free throw, which Gillispie ordered Perry Stevenson to goaltend. The Cats drew the T, but Gillispie decided he’d rather gamble on Georgia missing both free throws for the technical to ensure that his team got the ball back. Like Gillispie’s career in Lexington, the ploy was an epic failure, but it was worth a shot.

6. Sticking with the Right Batting Order

Everyone knows that if a player bats out of turn, he’s out. A weird situation popped up in a 2005 Kansas City Royals game, though. David DeJesus batted first in the first inning and hit a single. At that point, the umps realized that DeJesus was actually second in the Royals’ lineup and called him out. That meant the second man in the batting order had to come up to bat…David DeJesus. He flew out in his second at-bat. Fans of the Royals will tell you this pretty much encapsulates David DeJesus’ skill set: he’s so bad that he can make two outs in a single inning.

7. Keep that Rosin Dry!

Pitchers rely on the rosin bag to keep their hands try for an optimal grip on the ball, and MLB rules strictly monitor the use of the rosin bag. The ump-in-chief for a game is responsible for placing the bag on the back of the pitcher’s mound, and if it starts raining, the rules dictate that the ump is supposed to instruct the pitcher to put the rosin bag in his hip pocket to keep it dry.

8. Stay Off the Rims in Warmups!

This rule came out to bite the Harlem, Montana, boys’ high school hoops team last month. According to the state’s rules, players are not allowed to dunk during pregame warm-ups and can be slapped for a technical if a ref sees them throw one down. One of Harlem’s players found out during this spring’s playoffs that the consequences can be far worse than that, though. He hit a jam with such force that he shattered the backboard, which should be the high point of any high school baller’s career. According to Montana’s rulebook, though, if a player shatters the glass during pregame warm-ups during the playoffs, his team automatically forfeits the game. Don’t feel too bad, kid. You may not have won the title, but you broke the glass as a high schooler. You’re not going to have any trouble finding a prom date.

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