The Belgian, who joined the Bundesliga side on loan in the summer, has returned to Old Trafford after United summoned him back because of a lack of games with the 2013 Champions League runners up.
Januzaj, who has played four times for United this season and scored the winner away at Aston Villa, has made only 12 appearances for Dortmund, including just three starts. The 20-year-old has played six Bundesliga games, coming on as a substitute in all of them, and has not played a competitive game since featuring against PAOK in the Europa League a month ago.
Media in Germany have accused Januzaj of lacking the mental strength required to emerge at this level, while the Belgium team has told him he needs to play regularly if he wants to be included in the squad for the European championships this summer.
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