Pogba, De Gea and Bailly played the full 90 minutes in recent games against Manchester City, Feyenoord and Watford.
The clash with Northampton signals Man United’s third game in the space of a week, and Mourinho is reportedly keen to rotate his squad in order to keep players fresh.
According to the M.E.N’s Samuel Luckhurst, the triumvirate of Pogba, De Gea and Bailly will all be forced to sit out on Wednesday.
Resting Bailly, a stalwart of the United side this season, will most likely precipitate the reintroduction of Chris Smalling and Daley Blind as a centre-back partnership, but could also present the likes of Axel Tuanzebe and Timothy Fosu-Mensah with a rare chance to impress in the first-team.
The tie gives Mourinho, still in the process of figuring out his best starting XI, a chance to tinker with various formulas. He will, however, he conscious of the side’s desperate need for a victory after three consecutive defeats.