Manchester United are reportedly keeping a close eye on Rennes defender Mahamadou Nagida as they look to strengthen their left-back options ahead of the January transfer window.According to a report from TEAMtalk, the Red Devils have been impressed by the Cameroon international following several scouting missions, with the 21-year-old emerging as a serious candidate for a move to Old Trafford.United are keen to address their left-back problems, having struggled to find a consistent solution at the position. Diogo Dalot has been forced to play left in recent matches, highlighting the need for further reinforcements.Mahamadou Nagida could be an ideal defensive additionUnited believe Nagida has the potential to develop into an important player, with his pace, attacking instincts and defensive work rate making him an attractive option. The youngster joined Rennes in 2023 after developing at the Ecole de Football Brasseries du Cameroun academy and has continued to make encouraging progress in French football.The Red Devils have reportedly monitored him over the past six weeks, including during Rennes’ Europa League encounters against Juventus and Olympiacos. The feedback from those scouting assignments has been particularly encouraging.However, United are also considering several alternative options. Barcelona’s Alejandro Balde, RB Leipzig’s David Raum, Club Brugge’s Joaquin Seys and Bournemouth’s Adrian Truffert are among the defenders on their shortlist.Manchester United planning significant investment at left-backUnited’s interest in Nagida comes as Jason Wilcox and Christopher Vivell look to reshape the defensive department. The club could potentially recruit two left-backs across the next two transfer windows, with Luke Shaw’s long-term future also a consideration.Nagida signed a contract extension with Rennes until 2029, meaning negotiations could prove challenging if United decide to pursue his signature.Nevertheless, his impressive development and the positive assessments from United’s scouts make him an interesting option. A move to the Premier League could give the 21-year-old the chance to take the next step in his career.The post Manchester United step up scouting of Ligue 1 defender ahead of January transfer window appeared first on CaughtOffside.