“I want to tell you. I might as well do. About a boy who can do anything,” the Manchester United fans started to sing at matches midway through the 2013/14 season. “He comes from Belgium. His name is Adnan. Januzaj! Januzaj! Januzaj!”
A boy who can do anything; that's how United fans viewed Januzaj. And they were far from alone. “I genuinely think this guy could be one of the best in the world,” Gary Neville told EA Sports. “I think he's that talented."
Top European clubs agreed. As did a number of countries. The scramble for Januzaj soon began.
He decided to remain loyal to United, signing a five-year contract in October 2013, and later pledged his international future to Belgium despite being able to represent Albania, Serbia or Turkey. England were also interested.
Over the course of the 2013/14 campaign, Januzaj produced moments of brilliance on a regular basis. There was the brace against Sunderland on his first start, the excellent pass which led to United claiming a draw against Southampton, the instrumental display against Swansea City in January.
The 18-year-old was the shining light of a dour David Moyes side. Yet there were cautionary, almost prophetic, words from then Swansea boss Michael Laudrup after Januzaj's sparkling performance against his side.
“I hope he's the kind of player who knows he will have to develop more, not think that just because you've played ten games in the Premier League you're already at the top.
“Sometimes, unfortunately, players who play ten or 15 games at the top level are told by everyone that they're so great and they believe it. They think they're already in the top three in the world.”
Januzaj's debut season in the United first team ended with four goals and six assists in all competitions. An impressive return for someone so young. However, that campaign would be the high point of his time at Old Trafford.
The arrival of Louis van Gaal derailed Januzaj's rapid rise. The Dutch coach employed a rigid tactical structure, one in which individualism and flamboyance were not encouraged. It harmed the teenager, who had displayed great creative instinct under Moyes.
Januzaj started only eight matches in 2014/15. A change was needed the following season and Van Gaal felt a loan move away from Old Trafford would be best. However, he was left disappointed when Januzaj opted to join Borussia Dortmund.
Van Gaal felt Januzaj would struggle to get the regular football required there. He was right. The young star didn't start a single Bundesliga game and was sent back to United in January having drawn the ire of Thomas Tuchel.
"I believe in the talent of Adnan Januzaj,” Van Gaal said after Januzaj returned to United. “I have said this previously. But I also said that it shall be very difficult to play matches in Dortmund and, unfortunately, I was right.
“I think that, if he cannot play there, then he would be better training with us here to show his talent in the first team."
Januzaj, who was handed the No.11 shirt at United after Ryan Giggs' retirement, made only three further appearances that season.
In the summer of 2016, the Belgium international joined Sunderland on loan. At the Stadium of Light he was reunited with Moyes. In theory it was a smart move, although it's doubtful the Scot's rather pointed criticism would've inspired Januzaj.
“I've said to Adnan, you need to stop blaming everyone else for what's gone wrong,” Moyes said. “This loan's a little bit of a risk. I've told Adnan to look at himself and realise that it's down to him to change it; it can't always be the manager's fault or the coach's fault that he hasn't progressed.
“Adnan's got to ask has he prepared right, has he got himself in the best condition, has he trained well enough? And, when he's got his opportunity, has he played well enough? In a lot of cases the answer has to be no”.
Januzaj's spell at Sunderland was something of a disaster. The club finished bottom of the Premier League and he started, partly due to injury, only 18 times in the top flight.
And so, aged just 22 years old, Januzaj left United. He joined Real Sociedad in the summer of 2017, signing a five-year contract. He has since gone on to play 81 games but isn't a guaranteed starter.
Many will put his failings down to a lack of application; the classic story of a young player who was given too much too soon and losing their motivation.
Januzaj, though, has always insisted that is not the case. “These are the people that don't know anything about football,” he told The Independent shortly after his move to Sociedad.
“I don't care, I keep working hard. You can only go in one direction, and that is to shut those people up. Once you do it, they will look ridiculous. It will feel amazing, I will feel very good because those people were chatting s--t about me.”
Januzaj has yet to silence his doubters. Yet given he is only 25 years old there is still plenty of time to do so. And just remember, he could once do anything.