The Brazilian has started all but two games this term and has also chipped in with a couple of goals. The 22-year-old has been pulled up in the past for his over-exuberance in attack that has sometimes led to him getting caught out in defence, but his manager feels he is making big strides forward with his decision-making.
"Rafael was our best player on Saturday [against Stoke]," the boss told reporters at a press conference at Old Trafford on Monday.
"He's maturing and learning all the time and he's blessed with great enthusiasm to play. He has good skill, speed, determination... he has all the qualities and maturity brings all those qualities together. Bit by bit he's done that in the last two or three years.
"Last year and the year before he was impulsive, over-commiting himself. He knows that and we've been over it a few times. But he's maturing fantastically."
Rafael himself agrees. "I think mature is the right word. I've learnt to hold a little bit. I always want to know more and read the game more to find out what a player is going to do next. I'm definitely more mature.
"The way I play for United has changed a bit and maybe that's why fans are looking at me differently. I'm playing more maturely and I'm scoring goals as well. I hope I can keep improving."
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