United have already secured their place in the last 16 by winning their first four games in Group F, but they must beat Sporting to make sure they finish top.
Ferguson is also aware that Sporting need to win to keep alive their own hopes of making it through to the knockout phase, and he is anticipating an exciting match.
He told Sky Sports News: "We've experienced over the years that some teams come to Old Trafford and are inspired, while some teams freeze.
"The young players of Sporting may come here and express themselves, which will make it a really good game.
"We know they need to get a result, which is why I won't be putting too many of the young players in.
"That indicates a desire to make sure we win to give us that opportunity (to finish top of the group). We have to be fair to both sides (Sporting and Roma)."