United have managed a 100 per cent start int he Premier League this season.
Ferguson said: “Experience will be important against Benfica and that’s why my team might be different in Lisbon on Wednesday.
“Benfica are always a handful. We always expect a difficult game there and I watched a couple of their matches away from home and they were absolutely brilliant.
“There’s no doubt the younger players will get good experience in the Champions League this season but the important thing is to qualify.
“The home games will be better for them. Our first home game is against Basel and the young players are capable of playing in that type of game. Benfica away is one you have to respect.”