Ten Hag has named four goalkeepers in a 21-man squad to take on Bayern Munich in their Champions League group stage opener as they are without 12 players, with nine of the absences injury-related.
Mason Mount and Raphael Varane featured in team training on Tuesday morning but have not travelled to Germany while Harry Maguire is the latest casualty.
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Midfielders Kobbie Mainoo and Sofyan Amrabat trained separately from teammates at Carrington while Aaron Wan-Bissaka, Luke Shaw, Tyrell Malacia and Amad are long-term absentees.
Jadon Sancho is not under consideration for selection pending the outcome of his disciplinary issue for accusing Ten Hag of lying about his absence from the squad for the defeat to Arsenal 16 days ago, while Antony has taken a leave of absence amid allegations of domestic assault.
United did not register Donny van de Beek, a Champions League semi-finalist with Ajax in 2019, in their European squad. Travelling squad members Altay Bayindir, Radek Vitek, Dan Gore and Omari Forson have never played for the United first team.
Maguire was involved in training in the morning training session but suffered an unspecified issue, according to Ten Hag.
“He had some complaints and we have to see how bad it is,” Ten Hag said. “He finished training [today] but was not good enough to travel.
“Of course, it&aposs a concern but that&aposs why we knew that before and that&aposs why we constructed the squad with depth, so we can deal with it, the squad can deal with it and the squad can deal with it.
“I don&apost know if we have to go to the doctors or officials because they are dealing with the problems. First of all, injuries always come in top football because we&aposre living on the edge and when you&aposre living on the edge, injuries are coming up.