One last thought - someone mentioned a 200mm f2 --- a great lens but a disaster for sports because the depth of field is much to shallow.
I would have said the same until my sports photographer friend showed me images he had shot with his 85mm 1.2 of indoor volleyball. Can you imagine how razor thin his field must be? Same friend shoots outdoor nighttime soccer with a 200mm f1.8 (the predecessor of the f2.0) and he pulls out good images where I would have put away my camera long ago.
Yes, he is working with a very thin depth of field, but he's somehow figured it out.
One the subject of WB...I shoot an expodisc or gray card for a custom WB, but outdoors, lighting and conditions change. If I really want to save an image, Lightroom can often rescue the day...but WB has nothing to do with exposure.
