Kums worked with Januzaj before his move to United.
"Adnan was not a powerhouse, and not even the most explosive player," he recalled.
"But Adnan had other abilities. So he was like no other between the lines and he was always free. He was always busy with the ball. Dribbling to juggling and giving passes. He kept going.
"His father demanded much of his son, I think he had a lot to do with (his success)."
Kums continued: "Adnan was ahead of others for his age, but because he often played with teammates who were older he never once got the captain's armband, until I once gave him as a reward for his performance."
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