Manchester United benefitted from the return of Luke Shaw in late November, but he is now back on the sidelines. Amid the festive schedule and slow return to action in the New Year, there has been lots of focus on the exciting return of Lisandro Martinez and Casemiro, that one player’s absence has almost slipped by unnoticed. Luke Shaw has not made any of the past three matchday squads, against Aston Villa, Nottingham Forest, and Wigan Athletic. This week after the Wigan game when manager Erik ten Hag was talking up the four players he hoped to see back this weekend, he listed Shaw as just a p…