The 18-year-old is part of Manchester United’s squad currently on tour in the United States ahead of the new Premier League season.
Chong has managed to bounce back from a cruciate ligament injury to challenge Anthony Martial for a spot in the Manchester United team on tour.
The teenager came off the bench to replace the France international in Manchester United’s 1-1 draw with Club America in their first pre-season game stateside.
The Dutch starlet earned rave review for his stunning cameo against Club America as the right winger looks to stake a claim for a starting spot.
Speaking at his post-match media conference following their stalemate with Club America, Mourinho said:
“I have plans to make him train the most most possible times with us, because that increases his evolution.
“But he has to play where he belongs, he has to play in the academy and develop physically, because physically is where he’s not ready.
“Technically, he’s very good, tactically he understands the game and he understands his position, but by the physical point of view, when the game gets into contact situations, he’s in trouble, he’s fragile, he’s still a kid.
“But the talent is there, the personality is there, the passion to play, the humility to learn, so this is a fantastic experience for him.
“It depends on some cup matches. He’s one of the good kids we have, but it’s not for today but for the tomorrow – he’s a good kid.”
Manchester United ended up in second place in the Premier League table last season to secure their best finish since Sir Alex Ferguson’s retirement in 2013.
The Red Devils started their summer spending with the £17m addition of FC Porto defender Diogo Dalot to improve Mourinho’s options at full-back.
Manchester United signed Brazil international Fred in a £52m deal from Ukrainian Premier League champions Shakhtar Donetsk.
Veteran goalkeeper Lee Grant has also completed a switch to Old Trafford from Stoke City.
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