When writing stories about cheating in boxing, it is a stock trick for one to conceal something steel, typically a horseshoe, in one's glove. Or someone else might intimidate the boxer into cheating.
A character employing this tactic in non-professional contexts is probably a Combat Pragmatist
A comic variant is for the horseshoe to bend or break on impact, showing how tough the opponent is.
Interestingly, the point of a boxing glove is not to dampen the blow, it's to protect the hand. Hiding a horseshoe in your boxing glove would be just as likely to damage your fingers as your opponent's face. This simply makes it an Acceptable Break from Reality
- In Spy Versus Spy, one spy used this trick to pwn the other.
- Played for laughs in one issue of Little Archie. Little Jughead gives Little Artchie a pair of lead weights while they're training for a boxing match; he instantly refuses, saying "That's cheaing." Jughead informs him that the weights are only for training purposes; when they take the weights out for the real fight, his punches will be harder. Mr. Weatherbee brings some of his colleauges to watch the pair train, and Archie's glove slips off and hits Weatherbee in his Glass Jaw. The other teachers comment "wow, knocked out by an empty glove!"
- Happens in the Steampunk Halloween 2012 comic from Antarctic Press. A boxer fighting Dr Frankensteam's creation slips a horseshoe into his glove. However, the horseshoe shatters when her punches the monster.
- An episode of CSI: Crime Scene Investigation centered on a boxing match. The winner of the match was found to have injected mercury into his glove.
- In an episode of Blue Bloods a bunch of executives engage in boxing Fight Club. When one of them dies after a match, the detectives find that the winner's gloves have been doctored to make them heavier.
- In an episode of Malcolm in the Middle, Dewey carries a purse (or man-handbag) to school and is bullied by other kids on the way home for doing so. But then he swings it at one of the kids, and whap!--turns out he put a brick inside it.
- There's a minor charcter in Skyrim who boasts about winning a brawl by using a horseshoe as a knuckle-duster. Fittingly, his name is Irnskar Iron-Hand.
- In Fallout 2, you can make a name for yourself as a boxer in New Reno. During the boxing matches, you are stripped of all equipment and given a pair of boxing gloves to fight with, and any other attack will disqualify the PC. The boxing gloves deal very little damage, and the PC needs either good critical hits or dedicated damage perks to win. However, in the same city, you can find a pair of boxing gloves with plates slipped into the knuckles, allowing all but the last fight to be won by dealing hit point damage (it is possible for a character to be too weak in combat to do even that, but most such characters are disallowed from the boxing ring anyway).
- Aran Ryan, one of the boxers in the remake of Punch-Out!! has horseshoes in his gloves; this provides the picture for Trying To Catch Me Fighting Dirty.
- There was a Merrie Melodies cartoon where, after a boxer lands an especially telling punch, the referee stops the bout and checks the boxer's glove. Upon removing and shaking the glove, out drops a horseshoe... then three more horseshoes... then a confused-looking horse.
- In "Hare Trimming", Bugs pretends to be a French gentlemen rival to Yosemite Sam for the love of a rich widow. Sam gives Bugs "a taste of leather" and Bugs responds in kind... but not before putting a brick inside the glove. After hitting Sam, he shakes out the pulverized remains.
- "Rabbit Punch" has the boxer and Bugs remove their gloves. When Bugs removed his, horseshoes fell out of them.
- The Simpsons: In "The Homer They Fall" Homer sees that Moe has a boxing glove with barbed wire on it. Moe says "yeah, they don't let you use that no more."
- In the Donald Duck cartoon "Canvas Back Duck", Donald's nephews put scraps of metal in his glove, but it only makes the glove too heavy to lift. His hand slips off and his fist accidentally hits the other fighter in the jaw. Fortunately, the opponent had a "glass jaw" and is out like a light.
- On the Goofy cartoon "The Art of Self-Defense", two 18th Century dandies slap each other with gloves. During a break in the action, one of them sneaks his snuff box into his glove.