A lot of bile is directed at Semi-Pro because it's another sports comedy with Will Ferrell. This isn't a significant problem. If it was, people would also make note that co-star Woody Harrelson has been in White Men Can't Jump, Kingpin and Play it to the Bone. Ferrell is in a slump because he's stopped making movies for people other than himself.
Leading his amateur Flint, Michigan basketball team to possible membership in the NBA, Jackie Moon (Ferrell) only possesses traits already expected of Ferrell characters. The '70s-based setting hasn't the genuine feel it did in, say, Anchorman. Here it's an excuse for the stupid novelty of underscoring a white character with funk music (something Superbad just did.) The supporting players---Andre Benjamin, Maura Tierney, Will Arnett, Andy Richter---don't seem invested in the movie.
As with last year's Blades of Glory, Ferrell's indulgence reaches so deep, it no longer means anything. I can't tell you why Ferrell flipping out at a boardroom meeting and biting his hand is funny, because it isn't. Even the tone lacks uncertainty. Scenes of former lovers played by Harrelson and Tierney reuniting strive for a sincerity removed from the farce. Those bits end up the most laughable because there's little reason to care.