What arena? I assume you have press access and will be field level?
Do you want the bad news first? Unless it is amazingly well lit you are going to have issues with a f/4 lens. You want 1/500th minimum to stop action, but with semi-pro level athletes I think 1/640 is better. You are going to start at ISO 1600 and hope you have enough shutter there, a priority will be keeping your shutter at or over 1/500th, ISO is secondary.
You should use a variety of positions to obtain a variety of shots. Get there for warm-ups and play with your setting while you get some isolation shots of players warming up. I like to use my 400 in the endzone when play is within 30-40 yards, I like things coming at me at 400mm, and in your case the 200mm will prove helpful when they are within 15 yards as well. You can also set up on the sidelines to get a different angle on the play, mostly for QB/defender isolation and when the play is run towards you. BE sure to get the guidelines for the specific venue and event (by asking the other press there, or the venue staff), for example for NFL you cannot shoot from the 30-50-30 on the sideline or behind the bench, you will be escorted out or get slammed by a player. You also have to leave sight lines for the TV camera installations, which vary by venue.
In general you should be moving 10 or more times per game to position yourself relative to the action, and the other photographers there will be doing the same.
Monopod is essential.
