The 18-year-old winger put pen to paper on a five-year contract at the weekend before producing an impressive performance in the 1-1 home draw with Southampton.
Januzaj had previously underlined his huge potential by scoring twice in the 2-1 win at Sunderland earlier this month.
Jones, who started both games alongside Januzaj, told United's official website: "He's a terrific talent and it's an old cliche but as long as he keeps his head down, he can do great things for the club.
"There's massive pressure on him and he's only a young kid but it's testament to him that he's come in and done a great job.
"He threaded a brilliant ball for our goal against Southampton. He was sharp, he has nimble feet and he'll do great things for this club if he keeps working hard.
"He goes about his business quietly and if he keeps producing performances like that, he'll be a real star."