I have a football game Saturday the 8th, at night of course (damn it!) but I will take my 400 f/2.8 and see if that works much better, with less cropping. The thing I noticed about the 1DX is that I didn't need to give much AF time. I could just point the lens and shoot the shot, without a half-press sometimes and bang, it nailed the focus anyways. I suppose that would have more to do with the lens though too. My 1D4 was not doing that however, even with the same lens, and I cannot recall any DSLR that I've used that could do that. Cool camera!