According to ESPN, Man United are already scouting Rennes defender Mahamadou Nagida as a potential reinforcement at left-back.
The Cameroon international has risen through the ranks to become a key player for the French side, making 13 appearances in all competitions this season, scoring 1 goal and providing 2 assists.
Nagida is 1 of several left-back options on Man United's January shortlist, alongside Balde, David Raum, Joaquin Seys, Adrien Truffert and Jorge Salinas.