Imagine you manage a coven of baseball-playing vampires. The Cullen family is really strong this year and you want to bring in a ringer. Which currently active MLB baseball player do you sire?
But is it a vampire league or just a vampire team in a regular human league? Serious game scheduling issues if it is the only vampire team, can only really play at night or there is a good chance that you will need to replace more than just one player when all your players sort of combust walking out into the sunlight to play.
Also garlic on the ball would be pretty funny too.