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'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.
"I hope not scoring a goal doesn't come back to bite us," he said.
