The rule is that I randomize until each pitcher is either pink or red. I also try to keep the teams "even" in terms of condition. Sometimes this takes over fifty "rerolls" when you get two pitchers with the "bad mood" or whatever trait.
In the World Series I guarantee that both teams have the same quality starting pitcher.
Odds are fair, even if results aren't...
--
"Shut up and put your tinfoil hat back on." - Ulti