"He is playing better than he did two or three years ago because he has added composure, control and authority to his game," Fergie has told Radio cahnnel Key 103.
"What you are seeing is someone who has played for a long time and collected all these experiences together.
"Even at 35, Ryan is at his absolute peak as a footballer.
"Some players reach their peak at 28 or 29 and then fade a little bit, which is why they retire at 33 or 34.
"But Ryan has been at his peak for a long, long period.
"Ryan is fantastic. It is not just the example he shows on the football field, it is what he does off it.
"Every player in the club is saying to themselves 'How does that guy do it?' He is the living example of looking after yourself.
"The nutritional advice that is around today, the sports science and the training methods, give players a far better opportunity of playing well into their 30s now.
"Maybe people scratch their heads in wonderment at the achievements of the lad but he shows what can be done."