Its walkable mate, will take around an hour.
Exactly, stop worrying. Just google and it'll even give you a walking route so if there aren't buses, but there probably will be, just start walking.
Last year there were buses lined up after the match all with flight numbers on to go back to the airport. There's no reason why they wouldn't do the same this year, plus it's only a 10-minute journey not an hour, so if needed the buses can come back a number of times and do multiple trips.