In this case, you're pusing the camera to the limit ! You definitely need a tripod while shooting. In this case, you need to adjust your camera to the manual mode. And do the following checks:
1.Adjust the right aperture and shutter speed so that the picture don't get too dark or blurred. Under the low light circumstance, F2.8 or slightly more F-stop is appropriate. However, you must trade off the contrast and noise. Tripod is strongly necessary while you may go for any shutter speed that last long over 5 seconds. In addition, you can check this out, by pressing the shutter button half way. Therefore, you can view the right exposure whether the picture is under or over-exposure. In other words, this will verify whether you set the right shutter speed and aperture.
2.I don't suggest you move up ISO above 100. For most compact and even some DSLR camera, the picture's noise will be too much and picture result look pretty bad.
3.Make sure you select the right white-balance. The different frequency of light cause the camera taking picture differently. At the stadium, Tungsten is more proper.
That's all I can think of for now. Before the real event, get your hand on and test your camera. Good luck.
I just purchased a canon a85. it is a great camera. there are so many settings and i haven't had a lot of time to figure them out. I will be at a high school football game this friday and i need some suggestions on which settings to use. it will be dark out, but there will be stadium lights. i will probably be 50 to 70 yards from the field, there will be lots of action, i hope 
. should i use automatic? what about the highest quality setting? there are others such as outdoor, nighttime and all kinds of options. i have no idea which would be best. any suggestions?
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