I had fun shooting shooting the kids. My primary goal was to get some snapshots of my great nieces and nephews. They didn't get the ball very often. But, I still managed to get a few. lol
I thought the 5D's AF worked well enough for tracking to get some keepers, once your subjects got within a certain range.
Now, if you try to lock on subjects half way across the gym floor, it's going to struggle and misfocus a lot. lol
Here's another example with the 100mm f/2 following a moving subject (a shot of my great nephew).
Maxxum 5D, Minolta 100mm f/2, ISO 1600, f/2.2, 1/500 second
Here's a shot of a moving subject with a 135mm.
Maxxum 5D, Minolta 135mm f/2.8, ISO 1600, f/3.2, 1/250 second
Here's another one of the kids my brother-in-law wanted me to get some photos of (his stepdaughter's daughter, his grand daughter).
Maxxum 5D, Minolta 135mm f/2.8, ISO 3200, f/2.8, 1/400 second
I definitely got the feeling that it would take me more than one morning shooting to get good at, and it would take some practice to find the "sweet spot" for subject range to get a higher percentage of keepers, learning when the camera's AF is more likely to lock and track correctly from a given vantage point.
I had fun though. My brother-in-law and sister are coming over to visit later this afternoon. I'll ask him if they're playing this year, too. If so, I'll try to shoot a game using the A700 and see how much better it is for this type of thing.