Speculation over the 18-year-old’s future had been rife in recent weeks, with the Belgium born winger having been linked with a number of clubs, including local rivals Manchester City.
However, the youngster has now committed his future to the Red Devils following his sparkling display in United’s 2-1 win at Sunderland earlier this month, when he scored both goals.
“It’s a great thrill to be able to sign for Manchester United,” said Januzaj.
“Since arriving here I have always felt like this was the right club for me. This season has been great for me – going on the pre season tour, making my debut in the Community Shield win at Wembley and then breaking into the team at Sunderland – it’s like a dream.
“I want to work hard now and establish myself as a Manchester United player.”
United boss David Moyes also expressed his delight at seeing the winger commit his future to the defending Premier League champions.
“I’m delighted that Adnan has committed his future to United,” said Moyes.
“He is an outstanding talent and has impressed me consistently since I came to United in July.
“His balance, poise and ability to beat players is truly exceptional for a boy of his age.
“It’s great that he recognises that this club, with its tradition for developing young players and giving them a chance on the biggest stage, is the best place for him to be.”
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