i don't think i've ever watched a sports anime outside of Hajime no Ippo...
why? probably because I watch sports on TV. You know, I follow actual teams and watch their live events. I feel like there are two basic kinds of "sport watchers": those who watch a sport simply because they think the actual game/competition is interesting and those who watch a sport because they're following a team, often geographic or attachment preferences in play here.
I can see that those who fall into the first category for, say baseball, might enjoy Major or another baseball anime. But I don't see those who simply watch football for the sport in itself tuning in to Hajime or Major or Prince of Tennis, simply because they have no attraction to the sport.
People who fall into the second category (and I can't help but instinctively believe this is a majority of people, just because of how most sports leagues are structured) already have a storyline they are following for their sport(s) of choice: an actual team. I don't have any interest in sports anime or manga because I'm already viewing a sports drama when I read the papers every day to see how my team is doing or tune in for games.
I think my reasoning also makes sense when talking about sports manga. Obviously it doesn't hold true in all cases, but it's what came off the top of my head and makes ense to me... Also, and this applies for why people don't read manga in the first place, I think people have a preferred method of "getting" their input. Safe to say everyone on this forum has been raised in a TV-fueled society, where sound and fluid visuals are the norm. Manga, like books or radio, is simply "out of date" as a medium. And this is especially true for sports, where a great deal of the enjoyment comes from watching flesh and blood broadcasts, rather than reading about it in the news and seeing single snapshot highlights.
just my two cents.