OK. Now before I get started, please not that I haven't played football on a team. Yes, I've played it before. And yes, I've also played other sports (baseball, basketball, 10 years of jazz/tap/ballet/hip-hop/moddern :) dance classes).
With diabetes, I'm more of a runner than anything else now. Why? No clue; I just love running and exercising. Whether it be playing football or running, the key to doing well both in the sport and with your diabetes is just be aware of what is going on. Diabetes hasn't hindered my running abilities or speeds. As a matter of fact I've gotten better at running, etc., since being diagnosed.
Definately, sports will be different with diabetes than it used to be. Will it be harder or will you be any less of a player? Not one iota if you don't let it be.
Good luck, and I really admire your confidence to keep playing even with diabetes.
Let me know how it works out if you will,