Former United fullback Arthur Albiston says King has everything needed to make it as a Premiership striker.
The youngster has already made his first team debut this season and Albiston told the Manchester Evening News: "You have to be really special to make it as a player at Old Trafford and history has proved that you have to be extra special to make it through from the youth ranks as a Reds striker.
"But seeing the likes of Kiko Macheda and Danny Welbeck make an impact and get chances has given them all heart. Josh is 17 and from Norway and has typical Scandinavian attributes in that he is very level-headed.
"He is a good goalscorer and looks like a proper striker. He has good physique, two good feet and is very quick over the first 10-15 yards. He's got just about everything really."