New United signings Henrikh Mkhitaryan and Eric Bailly also started as they made their debuts at the DW Stadium.
Goals from Will Keane and Andreas Pereira gave United a 2-0 win.
Mourinho’s other summer signing, Zlatan Ibrahimovic, was absent. The Swedish forward is on holiday having played at Euro 2016 and, along with the likes of Wayne Rooney, Marcus Rashford and Chris Smalling, was unavailable following those international commitments.
The game was goalless at half-time but Mourinho made seven changes at the break, with Keane and Juan Mata among those coming on.
United then took the lead when Wigan keeper Jussi Jaaskelainen’s mistake allowed Mata to square for Keane to sidefoot home.
Just before the hour Pereira made it 2-0, firing home after Ander Herrera’s shot was blocked.
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