Manchester United have concerns behind the scenes regarding the stamina of their players.
The Red Devils are concerned that the players may just have run out of steam as the season nears its conclusion.
United are in a precarious position, as they need to win three of their last four games to secure a top four finish.
They have lost two in a row in the league in their battle for a Champions League spot, 1-0 defeats to Brighton and then West Ham United.
Per ESPN, manager Erik ten Hag has outlined the fitness of the squad in every press conference recently.
"It's the first time since Christmas that those players have a full week," he said after the West Ham loss.
"We have to reset, reload, get the energy back and keep going.
"But tiredness is in your head. If you want, if you have the willingness, you can take it. It's now up to the players, me and the coaching staff to be together, get the willingness in and the belief that we can take it and this team has it.
"You can't feel sorry for yourself, as a team stick together, as an individual take responsibility, make sure you have the energy, you have the focus, then play as a team and you get a result because we have proof of that all season."