The Brazilian defender hailed his strike in the win against the Merseyside club, and was happy to take the three points from what has been a difficult venue for the side recently
The sublime 51st minute strike brought the Red Devils level after opposing skipper Steven Gerrard opened the scoring - and Rafael said it was the best in his four-year stint at Old Trafford.
He also acknowledged that the timing of the goal was key, after his side initially failed to press home the one-man advantage brought about by Jonjo Shelvey's sending off in the first half.
"It's definitely the best goal I've scored for United," he told MUTV.
"It was a good moment to get it because it was so quick after they scored. If we hadn't had scored then we might have got a little bit nervous so it was an important time to get the goal."
The young right-back also reflected on the importance of picking up all three points despite a below-par performance, and of beating Liverpool at Anfield - a feat United have failed to achieve in the last five seasons.
"It's a very important three points," he added.
"It wasn't a great performance from us but in the last five years we haven't won here so we're very pleased."