The only current junior to watch is.. Borna Coric.
I saw him last year in Miami at the Junior Orange Bowl tournament, loosing the final in a tight 3 setter.
The kid has some serious potential, I have no doubts he will have a major breakthrough in his career.
He is one of the best if not THE BEST 14 yo junior. Many experts talk about him beeing a future star.
Just noticed that he won a G4 event in Mostar (dont know exactly where that is, but it´s his first junior title.)
I´ll definately have an eye on him.