We American baseball watchers take for granted the existence of the DH rule, and the fact that it only applies to half of major league teams (the AL).
But when you think about it, it’s AWFULLY weird to have a major national professional sports league where half the teams play by one set of rules and the other half play by a very clearly distinct set of rules.
Are there examples anywhere else in the world of sport where this is the case? (I wouldn’t be surprised if there are examples that are similar which involve moving from national to international competition… for instance, slightly different cricket or rugby rules in different parts of the world, and some compromise being reached for big international competitions, but that’s different from the AL/NL which are both clearly parts of MLB.)
The “NWA Rule”–any wrestler throwing his opponent over the top rope is automatically disqualified. Titles cannot change hands on a disqualification. Non-NWA affiliated promotions did not observe this rule unless it was convenient to do so for storyline reasons.
The “WCCW Rule”–titles could change hands on a disqualification.
The “Freebird Rule”–any two members of the Freebirds stable could defend the tag team titles in any given match. Sometimes extended to include other stables. Other promotions would either require a team with one member unable to compete to forfeit, or the one available member to defend in a handicap match, or allow a substitute partner.
In fact it is not. Whenever there have been two distinct major professional leagues, there have often been rule differences.
For instance, the ABA had a three-point arc, where the NBA did not. The AFL had two point conversions; the NFL did not at the time. The WHA used shortened overtime periods to settle ties in the regular season; the NHL didn’t, at the time.
Where baseball’s different is not in having leagues with different rules, it’s in maintaining a stable structure of two leagues for as long as it did.
The closest analogue is the “designated striker” (libero) in volleyball, who always plays in the backcourt and specializes in handling serves (and thus is usually of short stature).
I guess the question is whether people think of big league ball as one league with two subdivisions, which for historical reason have somewhat more cultural distinction than, say, the western and eastern division of the NBA, (I certainly do); as opposed to thinking of it as two distinct top level leagues which have a tradition that the champions of the two leagues, who have already achieved the championship of their league, meet in a further “world series” to determine the champion-of-champions.
In NCAA football, there is the Hawaii rule, where teams that play Hawaii can schedule an extra game for that season. In fact, Temple is trying to add a game at Hawaii **during **the season in order to become bowl eligble for this year!
For most of baseball history it really was two leagues. They had separate Presidents and were separately incorporated. They shared resources and such but they were distinct organizations - which is why the AL has the DH and the NL does not. The owners of the American League voted to institute the DH. The owners of the National League didn’t.
Today that distinction is effectively gone; the two leagues legally merged in 1999. The “different leagues” distinction is now artificial, essentially a PR sop to baseball fans’ traditionalist streak.
There’s also ECW rules, which pretty much meant no rules. No count-outs or DQs. I don’t remember if pinfalls counted anywhere. WWF started copying this format for awhile, but went back to their classic rules.
Next year there will be interleague play all through the season. That’s because both AL and NL will have 15 teams so they need to do that to make sure teams can fit in 162 games.
On a related note, when the NHL went from 1 ref to 2 refs, they phased it in. For a few years , each team played some games with 1 and some with 2. The number with 1 vs. 2 were the same for every team. They made the change in the late 90s
You asked for Professional but hear a NCAA analogy.
Back in the early days of the 3 point basket in NCAA B-Ball, the individual conferences set the distance of 3 point arc. They later had a consensus on the distance.
The Big East Conference had at least one year with 6 personal fouls before a player fouled out of the game.