The Portugal international scored a superb header in the 30th minute to cancel out Danny Welbeck’s opener and leave the last-16 tie finely balanced at 1-1 after the first leg.
Ronaldo chose not to celebrate his goal out of “respect” for his old employers, and Carrick hailed the Madrid talisman for his decision.
“Fair play to him for being respectful like he was,” Carrick told Sky Sports.
However, Carrick admitted the Red Devils were disappointed to concede a goal in the first leg, although the midfielder was satisfied with the visitors’ response to the setback.
“It’s never nice conceding goals anyway but it was a bit of a simple goal to concede really – a cross and a free header,” he added.
“But we moved on and we were strong for the rest of the game.”
Phil Jones, who earned plenty of plaudits for his display, also felt United could have done more to prevent Ronaldo scoring against his old club.
“We should have probably stopped the cross earlier. We know he can do that and we know we’ve got to stop that,” he said.
“He’s a fantastic player. You know he’s going to create chances at some point in the game, it’s just how many he gets.
“Tonight he didn’t get too many, and we’ll try and do the same at Old Trafford.”
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