I had a vague idea a few days ago that there should be an rpg where the pc's are players on a sports team, whether it be a real life sport or some kind of futuristic Rollerball-esque bloodsport.  There's a pro wrestling rpg called Kayfabe out there that has an interesting mechanic where the GM is playing as the wrestling company promoter, trying to build it up from the ground up.  Using mechanics like that and something like Rune's method for generating stats for enemies to generate opposing teams could be a very fun, very gamist experience. 

Templates could be used to 'theme' the opposing teams.  A team known for its speed could have a bonus to speed, a team known for vicious backstabbing could have spiffy built in ways to cheat, etc. 

The problem with a game like this is 'if the GM is motivated to build the team up, why would he throw obstacles in the way?'  I'd like to see reasons for adventuring off the field.  Maybe some kind of risk/reward system for the GM, where he builds a scenario that puts the players in danger and it rewards him somehow with points or whatever to build the team.  "Hey, if I have the mafia menace my players off the field, it gives me enough points to hire the ultra-distracting cheerleaders..."

Would there be interest in a game like this?  Any advice for developing the concept?

Eric

As an avid fantasy sports fan, and someone who occasionally dabbles in the Wrestling "RPG"-type games, I've also wondered about a concept similar to this.  My thought more revolved around each player owning a particular team in a given sports league, of which the GM was the Commissioner.  Either idea has merit, and also opens up a world of both possibilities and more questions.

Like you said, the initial ideas are very vague, and even if the concept was developed further, I'm not certain there's a market for such a game.  I am intrigued that at least one other person had the same thought, though.

You are talking about what the players will do in the game. But what would be the stories of the characters about? What are the characters going to do in the game that make it interesting to play those characters?

About mechanics to keep a franchise on-going, do you know the game In-Spectres? In this game the characters are working in a company of ghost-busters. It keeps the franchise economy linked to the adventures of the characters, which are their work as ghost-busters.

A couple of things to look at that might provide inspiration on how to mix the sports with outside adventure:

The Battle Angel Alita Manga, specifically the later issues that deal a bit with

The original Rollerball (and I suppose the remake if you must ;) )

the Speed Racer cartoon

Any of the many awesome and awesomely bad deathsport movies from the 60s through the 80s (deathrace200, deathsport, etc)

For game inspiration look at Habet Hoc Habet (gladiatorial miniatures) and Ben Hvrt from cheapass games (not to mention the many and varied Stratomatic type sports games).