Fergie struggling for defenders in Milan
Inter coach Jose Mourinho expects United to go on the defensive at the San Siro and thinks the tie will only be decided at Old Trafford on March 11, possibly in extra-time.
Ferguson, however, said he wants his side to express themselves in the first leg.
"I'm sure Jose has seen us enough to know that we seldom go into a game not trying to win and it won't change tomorrow," Ferguson told a news conference on Monday.
"We won't be changing much...perhaps one positional change different from normal, but otherwise we'll play in the normal way.
"I think it will be decided tomorrow, if we score we'll have a great chance. If we score an away goal it will help," the 67-year-old added. "It would have been a great final, I don't think it will go to extra-time (at Old Trafford)."
United are without the suspended Nemanja Vidic and fellow defenders Wes Brown, Gary Neville and Rafael have been ruled out through injury.
John O'Shea and Jonny Evans flew out to Milan despite also carrying knocks.
"Obviously we have some injury problems, we won't know until tomorrow. It's a worrying moment for us," Ferguson said.
O'Shea is the most likely to be fit but if the Irishman and Evans do not recover, there are no obvious choices to partner Rio Ferdinand in central defence against the Serie A leaders.
"The options are panic," Ferguson joked. "I'm hoping one will make it."
The other defenders in the squad are left back Patrice Evra and youngsters Fabio da Silva and Richard Eckersley, who are full backs and have barely featured for the first team.
Ferguson, who picked out Inter striker Zlatan Ibrahimovic as the dangerman, will renew acquaintances with Mourinho on Tuesday for the first time since the Portuguese left Chelsea in 2007.
Mourinho, whose Porto side knocked United out on their way to winning the Champions League in 2004, has got the better of Ferguson most of the time, winning six, drawing five and losing one of their 12 meetings.
"I didn't change in the last 12 games so maybe I should change," Ferguson said when asked again about his formation.