Ronaldo made the breakthrough with his 36th goal of the campaign to leave Roma stunned after 39 minutes of Tuesday night’s quarter-final first-leg tie at the Stadio Olimpico.
And after soaking up pressure, Rooney extended United’s lead after 66 minutes after a defensive mix-up in the six-yard box.
It was a marvellous show of composure from United, who went into the match on the back of six straight Premier League wins.
Given they had taken four points off Roma in the group stages this season, it was little surprise they approached this match with confidence.
United, who meet Roma again at Old Trafford next Wednesday, could be set for a semi-final against Barcelona, who won 1-0 away to Schalke.