The 39-year-old ensured the Red Devils would leave London with three points on Saturday, striking home 10 minutes from time to wrap up a 2-0 win over QPR.
Giggs' performance at Loftus Road belied his years and impressed fans, pundits and team-mates alike.
"He is an unbelievable player," United right-back Rafael said.
"Every game you see him he works hard, scores, makes assists. It is getting boring. He is just such a good player. He is the same in training; he just loves to play the game. He is one of the top players that I have played with.
"He gives us experience, confidence, and when you are feeling bad he comes and helps you, especially young players.
"Sometimes a young player finds it tough going and he helps them to show how to do it. He knows it from playing for 22 years.
"He pulls the player aside. He spoke to me a lot when I was young."