United saw off Bolton 2-0 at Old Trafford thanks to two early goals from Ronaldo, captaining Sir Alex Ferguson's side for the first time.
Trotters boss Gary Megson admitted his players were still in awe about the quality of Ronaldo's free-kick, saying: "It was genius from probably the best player in the world at the moment. Everyone in the dressing room afterwards was talking about how he does it. We have seen him do it twice now and the truth is we just don't know how he does it."
Ferguson believes the title race will go to the wire and heaped more praise on his skipper for the night.
Ferguson said: "The important thing was that we had the opportunity and the incentive to go three points clear of Arsenal, our nearest pursuers.
"It's nip and tuck now. I think it's going to go to the wire. Chelsea will be key because they have got us and Arsenal at home.
"It's a lead, it's not a significant lead but it's a lead nonetheless. With eight games to go the team who plays with the most consistency now will win it."
Ferguson made seven changes from the side who beat Derby and claimed he needed to test out various options ahead of Sunday's meeting with Liverpool.
Gerard Pique came in for the injured Rio Ferdinand while Wayne Rooney, Paul Scholes and Ryan Giggs were all rested.
It was not a great performance but it was necessary to make those changes as Rio Ferdinand is doubtful for Sunday with a back problem," added Ferguson. "I had to find out about Gerard Pique. We've got great confidence in the lad and he's come through very well. They are all top players so you have to put your faith and trust in them."