The Times is reporting that Mourinho wants to land at least one new full-back in the summer transfer window and that the Red Devils have been monitoring the progress of the 17-year-old Sessegnon all season.
The teenager has been in brilliant form for Fulham this season and has scored 15 goals in all competitions to help Fulham challenge for promotion back to the Premier League.
Manchester United are understood to be on the lookout for a new full-back because Antonio Valencia is set to turn 33 in August and Ashley Young is more suited to a role on the wing.
Sessegnon has been attracting interest from a number of clubs with his fine form, with the teenager having notched up six assists in 44 Championship games this season.
Manchester United are bound to be linked with a host of players in the coming weeks and months as Mourinho looks to assemble a team capable of winning the Premier League title next season.
Meanwhile, the Red Devils are currently preparing to take on Arsenal in the Premier League at Old Trafford on Sunday afternoon.
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