Ryan Giggs says the Reds were relieved to see Dimitar Berbatov strike a second half killer blow during the Boxing Day win over Sunderland after the Reds had initially threatened to run riot.
Sir Alex's men had taken a 5th-minute lead through the Bulgarian striker who headed home Wayne Rooney's cross at the far post. A second goal looked inevitable before the break as the Reds piled forward in numbers, but were denied by the woodwork (twice) and Sunderland stopper Craig Gordon who saved well from Rooney and Ryan Giggs in quick succession.
United had to wait until just before the hour-mark to double their advantage and effectively kill off any hope the depleted Black Cats had of stealing something.
"You're always a bit nervy when you're up against a very good Sunderland team and it's only 1-0, but once we got that second goal it was comfortable," Giggs told MUTV.
"We played really well in the first half an hour and created a lot of chances, just as we did against Blackburn. The difference that day was we were putting the chances away pretty much every time we went forward and it could have been the same today. The goals just didn't come though and we were a bit disappointed to come in at half-time with the score only at 1-0.
"As I said though, once we got the second we were comfortable and we were happy to see the game out knowing that we've got a game in a couple of days. We didn't want to go flying about and pick up any injuries."
Berbatov's second goal of the game - aided by a huge deflection off Anton Ferdinand - was his 14th of the season and seventh in his last three games. Giggs was full of praise for United's top scorer who again looked sharp and hungry throughout.
"Berba is playing really well," added the veteran midfielder. "He's scoring goals, good goals and when you're a front player that's what you want to do.
"He's getting himself in positions where he's getting chances and he could have even got a couple more today."