The Group H leaders, who flew out of Manchester on Tuesday afternoon, secured a come-from-behind victory over the Portuguese side two weeks ago at Old Trafford and know a win in Braga will secure a place in the last 16 of the competition.
Sir Alex told ManUtd.com a fortnight ago he'd consider Saturday's subsequent trip to Villa Park and weigh up his midfield options in particular when picking his team to take on Braga.
"My team selection for Braga will reflect the game we play afterwards, Aston Villa away, so I’ll change the squad around," the manager said.
"Think, for example, about the midfield options I’ve got. This is an area where some people say we’re weak but I’ve got Darren Fletcher coming back from illness, Tom Cleverley developing as a player, young Nick Powell improving, Anderson back fit and looking terrific, plus Paul Scholes, Michael Carrick and Ryan Giggs. I’ve got heaps of midfield options now.
"In the wide positions I’ve got Ashley Young fit again, Nani and Antonio Valencia. Then I’ve got the strikers. My area of worry for a long time now has been the back four.
"I haven’t had great options so far this season in defence. There’ll be an option with Alexander Buttner – that’s maybe the one that will definitely happen. I’ll need to see how we are in terms of a centre-back pairing for that game. But away from home in Europe you really do need a bit of experience so it’s likely that it will still be Rio Ferdinand and Jonny Evans.
"At right-back, Rafael’s fit and his form this season has been absolutely fantastic. So I’ll