The Belgium international made his second appearance for the Red Devils since returning from a loan spell at Borussia Dortmund on Sunday afternoon.
Januzaj has been contending with an injury since his return from the Bundesliga club and Marcus Rashford has established himself as United’s latest teenage sensation.
The 21-year-old scored United’s winner in a 1-0 victory over Aston Villa at the start of the season before his temporary switch to Dortmund.
Former Scotland international Nevin believes Januzaj can still blossom into a good United player despite his Old Trafford career stalling in recent seasons.
“The signs for him when he walked into the Man Utd side were extraordinary,” Nevin told Newstalk.
“He looked like a better technical footballer than Rashford. Nothing has happened. He has hit the buffers. He is still a very good player.
“He is nowhere near the standard we expected to happen. I am sure there is a very good chance he will come back.”
Januzaj scored four times in 27 Premier League games in his breakthrough season in 2013/14 under David Moyes.
However, the Belgian forward has only netted one Premier League goal in the next two domestic campaigns.
United host Watford in the Premier League on Wednesday night.
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