Don't be afraid to set your own shutter speed and aperture for sports. You'll have much more control over the appearance of you photos. My strategy is to set an appropriate aperture to capture in-focus action with nicely blurred backgrounds with enough shutter speed to reasonably stop motion. My Nikon D800 has an Auto ISO setting that I engage to insure proper exposure particularly when outdoors shooting sports partially in sun and shade. Auto ISO allows me to get proper exposure.
Nikon D800, Nikkor 300mm f/2.8 lens, Aperture setting f/4, Shutter speed setting 1/1600s, ISO 500 (Auto ISO)
