Holders United came away from the San Siro with a 0-0 draw in the last 16, first-leg after dominating for long spells and forcing goalkeeper Julio Cesar into some smart saves.
Inter failed to find top gear but coach Jose Mourinho knew it was a decent result given an away goal in Manchester on March 11 could be priceless.
"This goalless draw is a difficult result for us because we can't lose at Old Trafford but also for them because with a score draw we will qualify," the Portuguese told reporters.
"This result will put pressure on both teams."
Inter are nine points clear at the top of Serie A because they have an uncanny knack of scoring at the vital moment.
Whether it be a piece of magic from Zlatan Ibrahimovic or a lucky, bundled goal in the last minute, the Italian champions are adept at turning average performances into good results.
They will struggle to play as badly at Old Trafford as they did in the first half on Tuesday so the chances of grabbing an away goal increase.
LACK OF PACE
Inter's problem though is a general lack of pace compared to United and even if the holders leave gaps at home, the Italian champions are not best equipped to exploit them.
"They have an intensity to their game we don't have. They are sprinters," said Mourinho, who has an excellent record over United from his time in charge of Porto and Chelsea.
Set pieces remain Inter's best hope and United boss Alex Ferguson was so worried about their height advantage on Tuesday that he played the tall Dimitar Berbatov instead of Wayne Rooney to try to neutralise the threat.
Rooney will be back at Old Trafford but Ferguson is well aware the Premier League leaders have wasted an opportunity to put one foot in the quarter-finals.
"I hope not scoring a goal doesn't come back to bite us," he said.
