Ronaldo, 36, could make his second debut for United this weekend when United face Newcastle at Old Trafford having returned to training with the club on Tuesday.
The Portuguese superstar returned early from the international break in order to be in contention for an appearance on Saturday afternoon and doesn’t want to waste any time before he gets back into action.
Ronaldo is already leading by example with his approach to training and Fred believes it is having a positive impact on a squad that has not won a trophy in over four years.
“It’s so good training with Cristiano, he is a very good guy, the best player you know about,” Fred told United Daily.
“We are so happy to have Cristiano here with us, and I hope he can bring us many titles at Manchester United.
When asked if he looks sharp in training: “Of course, yeah! He is an amazing player, you know the difference when you look at Cristiano Ronaldo.
“With the ball, without the ball, he works a lot and it’s so good for us. We are so happy to have Cristiano here.
“We know who Cristiano Ronaldo is because he likes to win, he pushes everyone, so you need to be at your best to get with him.
“It’s so good for us because he pushes everyone, we can win every game, so it’s so important.