Birmingham's Caldwell: Man Utd defender Jones can be best in world
Caldwell was impressed by Jones in last night's defeat to Manchester City.
"Jones is superb. I first saw him couple of years ago when he into the Blackburn side and he looked so strong and powerful for a young boy," Caldwell told talkSPORT.
"I don't know where his best position is going to be, but at centre-half his pace and power is so impressive in that area. And he's very comfortable on the ball.
"He could be one of the best centre-halves in the world once he matures."
And Caldwell insists the 21-year-old England star has the perfect mentor at Old Trafford.
"He'll learn a lot from Rio Ferdinand," he added. "He is such a calming influence and there's no-one better than Rio when it comes to positional play."