Jones ended a ten month absence from the first team with a confident performance during Man United’s 3-1 win over Swansea City back in early November.
Since then, the 24-year-old has mounted an unlikely resurgence under Mourinho, featuring in seven of United’s last eight games.
Mourinho, speaking ahead of United’s upcoming game with Crystal Palace, was full of praise for the Englishman.
“I am surprised how Jones has coped because, even with me, he had this injury that stopped him for a long time,” Mourinho said.
“He was recovering first with people he trusts in the medical department.
“Then he was working hard with one of my guys for a few weeks before he joined us, and he had a big improvement in his physical condition.
“Now he looks fresh, and strong, and fast and agile. He has played six matches and I do not remember the last time he did that.”
United fans are witnessing a side of Jones that hasn’t been seen since the Sir Alex Ferguson era – a side, it should be noted, that was considered a thing of the past by many critics.
That raw, unyielding sense of aggression at the back, underpinned by a quiet sense of cold determination, has made its way to the forefront of Jones’ game. The Englishman’s unwelcome habit of throwing himself into bad tackles and consequently injuring himself has led to months on the sidelines in the past. But since his return, Jones has espoused a level of maturity, almost as if his footballing brain has finally caught up with his physical ability. The result, as United fans have seen, is hugely encouraging.