The Premier League giants will head into the clash at Old Trafford with two wins out of two in Group H, while Braga have won one.
"Braga are a good team," the midfielder told PA Sport. "You have to respect them for getting to this stage to start with.
"It is not easy in any league to go through the whole season near the top [and qualify for the Champions League]. You have to respect them.
"They are going to be of a certain standard and we have to match it."
In the other game in Group H on Tuesday, Galatasaray will host Cluj.