Just found this on Tesco Direct, Battlefield 4 for XBox One available for just £8, home delivery only unfortunately, but still a good price for a physical copy of the game.
May be useful for someone on here.
Update, credit to Yas who posted this:
Please note: delivery is free for £10 and over. So you can get 2 for £10 - a fiver each rather than £8 for 1. Or you could top it up with any other game of course