Rules/features that only one sport has

Can’t think of any other sports but bodyweight is used to break ties in weightlifting.
Lighter lifter wins due to lifting more in proportion to bodyweight.

Yes, but they work the regular game as well as each overtime period on a clock, and there’s no back and forth of regulated innings.

Been said, but NHL hockey rinks are not all the same size. Hard to tell from tv, but true.

Boxing rings also don’t have standard dimensions. Boxers can even contract for the size of the ring that will be used.

All of Yankee Stadium, then. For the first time in history, the World Marathon Champ will also be the Heavyweight Champ.
:smiley:

This very occasionally occurs in baseball and I assume in cricket as well, but …

Fist fighting …

Any sport other than ice hockey, a player’s gonna get booted if they take a poke at someone.

Does any other sport have rules against Stabbing … seriously … 5 minutes in the penalty box for trying to stab someone? I do believe every other sport actually takes stabbing implements away from players before the game.

Is there another sport other than lacrosse which has formally designated offensive and defensive groups within one team that are on the field at the same time, with specific rules that only apply to one or the other? [Aside from goalkeepers].

International volleyball has the Libero.

I think the answer to this is “cricket too” but I’m going to post this anyway…

Is baseball the only sport where the defense has no possible way of instantly becoming the offense (like an interception in football/basketball).

Any sport without defense; bowling, golf, auto racing …

The rule is called “Spearing.”

I would think if the game inherently involves players carrying sticks, you need a rule saying you can’t poke someone with your stick. Lacrosse also has a rule against spearing.

Dentistry?

Um, yeah. Sure. That’s it.

Well duh lol.

I meant of sports that actually HAVE defense

The basic offense-defense-innings structure of baseball is very similar to Cricket.
There’s a sport called Netball, which used to be called “women’s basketball”, which has a weird-to-American-eyes rule, in which the court is divded into various zones, and different players are limited as to which zones they can go into. Also, like many sports, after a goal is scored the ball is returned to the middle of the court and play restarts, but instead of the ball starting out possessed by the team that was just scored on, the starting possession alternates.

Elephant polo has some interesting and unique rules:

7. ELEPHANT LYING DOWN IN GOALMOUTH
No elephants may lie down in front of the goal-mouth. To do so will constitute a foul. A free hit shall be awarded to the opposing side from the 20 metres semi circle in front of the goal, with only one elephant defending in the D and at least 15 metres from the spot. All other defending elephants must be 15 meters from the spot, but outside the D.

8. USE OF ELEPHANT TRUNK
An elephant may not pick up the ball with its trunk during play. To do so shall constitute a foul. A free hit shall be awarded to the opposing team from the spot where the ball was picked up. The defending players shall be 15 metres away from the spot.

9. FALLING OFF
If a player falls from an elephant, the play is stopped while the rider remounts. In case of injury, where the player cannot continue, a replacement may be called upon from among the reserves nominated, at the beginning of the Championship. Play is commenced with a throw-in by the Umpire between two elephants – one from each team, similar to the start of the game, but from the spot where the ball was when the player fell off. All other elephants shall be 15 metres from the spot.

13. PICK-ME-UPS
Sugar cane and or rice balls packed with vitamins (molasses and rock salt) and water, as needed, shall be given to the elephants at the end of each match; and of the end of the morning games soft drinks for the elephant drivers.

But all NHL rinks are the same size.

Right you are:

And one needs to make contact to draw the major penalty, it’s only a double minor if one misses.

Top level curling matches use the same structure; if there’s a tie at the end of regulation, extra ends are played until there’s a winner. It would be rare to go more than one extra end, though. Scoreless ends are relatively common during the game, but they are done on purpose for strategic reasons (and perhaps that’s unique to curling). If one point would win the game, one team or the other is almost certain to score something.

Curling is rather like golf in that players are expected to call fouls against themselves. There are officials watching each match, but they will generally let the players work things out among themselves.

One rule that’s probably unique to curling is that if a stone breaks, the largest piece counts. (I found one reference online that this rule may have been changed. And in any case, I’ve never seen, or even heard of, a stone breaking.)

That’s because you’ve never played overhand curling.