A very quick and easy way to get the WB very close to what it should be at an indoor basketball game or a football game is to use the Kelvin White Balance setting in your image. How do you know where to set it? Use live view and look at your LCD. Adjust the Kelvin setting until you see on the screen what you see in real life. Bingo. You’re set and the WB will remain the same throughout your shooting.
There won’t be any fluctuations and this makes post processing much more simple. There is a caveat however. This is assuming the light isn’t changing. An indoor sporting event and night football game where the game starts under the lights when it’s totally dark out and ends that way will be great for using the above set-it-and-forget-it method.