The 19-year-old winger starred for Warren Joyce's reserves, proving his clinical touch in front of goal, and with first team coach Louis Van Gaal in attendance, his efforts are unlikely to have gone unnoticed.
A surprise inclusion, considering he featured for the senior side in their 4-0 victory over Queens Park Rangers just one day previously, yet Januzaj took full advantage of the occasion, getting on the score sheet, not once, but three times.
Each strike proved simple, but well-taken, nonetheless. He bagged two in the first half as United entered the break three goals to the good, before rounding-off a comprehensive win with his third in the second period.
Even prior to this performance, the footballing world will have been well aware of Januzaj's potential. Nonetheless, this match serves to prove that he is head and shoulders above the level he was playing at just a season ago.
His meteoric rise from youth football to first team action, aided by the faith of former Red Devils' manager David Moyes, was truly outstanding, and ultimately it seems a shame to witness his talent going to waste.
However, it's also very difficult to see him breaking into Van Gaal's strongest starting line-up, especially on the back of the team's weekend performance.
Januzaj has experienced just 104 minutes of action, split across four appearances, thus far, and his spell on the side-lines looks set to continue for the foreseeable future.
Nonetheless, tonight's display is certainly something for Van Gaal to mull over. After all, the Belgian youngster's incredible potential will surely excite the Dutchman.