Challenge mode does get a little tedious (I especially hate Pink Yoshi's mission, ok that was random), but I got so many fail moments in Mario games just from Super Sluggers. One time was me, as Baby Luigi, smacking a Pianta with a baseball, making the ball fly, and got a home run from that. The replay was priceless.
I think it's because Mario Superstar Baseball didn't sell well.
Err, it didn't sell well, because that game turned into a non-existing game.
I mean, it was released for Gamecube, but a few weeks later, there was no shop available, knowing about the game's existence in Europe.