Although it's hard to compare one sport to another, we're going to attempt a definitive ranking of the best sports manga of all time. Vote up your top sports manga titles regardless of how much you actually enjoy that particular sport. If one of your favorite manga in the sports genre is missing from the list, you can also add some of your own titles to make the list even more expansive.
No matter what sport you're into, there is a manga for it. Is basketball your sport? Check out Kuroko's Basketball or Slam Dunk. Maybe you're more into baseball? Try Cross Game or Diamond no Ace. There's even a great football anime in Eyeshield 21, despite the fact that American football isn't even that big in Japan. Vote up your favorite sports manga, and downvote any titles that you wouldn't recommend to other readers.