Manchester United have a first team stretched with injuries especially in defence. The academy could provide a solution to these problems. A succession of injuries in defence have made this season a constant struggle for Manchester United. Right now there are four centre-backs out injured and two left-backs. Erik ten Hag is working with what he has available. Willy Kambwala stepped up against Liverpool, making his second ever start. The young Frenchman was impressive in the 2-2 draw. READ MORE: Manchester United’s Best Academy Players of All TimeManchester United youngsters on the benchManches…