I've recently returned from a watersports holiday where I was disconnecting two or three times a day for at least an hour. My consultant advised to test before the sport, if over 12 have a small (for me 0.5 to 1.0) bolus before starting. If lowish, then have a small amount of extra carb. Wait until an hour after the end of the session, then test & if high, have a small bolus.
Remember, football is both anaerobic & aerobic & your levels may rise with anaerobic exercise, though they'll fall with aerobic exercise. It's confusing & complex!
Also remember that the disconnection will not result in an immediate rise as insulin being infused between 14:00 & 15:00 for example, will be working its hardest (for most people) from 15:00/15:30 to 16:30/17:00 so the effect of being disconnected isn't seen until a couple of hours later. Add the effect of hormones released during exercise into the mix & it's a nightmare!
From personal experience, I say be pragmatic. I find that the nurses are cautious & tend to work to tight rules, but when I discuss the same issues with the doctor they're always more inclined to help you fit the treatment round your life & not vice versa.
In essence, being unplugged for a couple of hours once a week won't harm you as long as you have the discipline to test 2 or 3 times in the hours following exercise & calculate adjustments, considering insulin on board potential, post-exercise glycogen replacement, etc etc.
I've been there & still struggle somewhat, but time, effort & sore fingertips will make it work.
Two websites of interest:
www.diabetesnet.com &
www.Runsweet.com both have useful info on exercise, the former is a US site so you may need to convert from US measures, the latter has useful info, but is badly laid out & difficult to navigate.
Good luck.