Manchester United manager Jose Mourinho said Paul Pogba could perhaps explain the poor form that has cost the midfielder his starting spot.
Pogba has started just four of United's past 11 games in all competitions after a worrying dip in form.
"Ask him. Ask him when you get a chance what he thinks about it," he told reporters.
Pogba, 25, suffered a hamstring injury in September, seeing him sidelined for two months.
However, Mourinho said that setback could not be used as a reason for Pogba's form.
"It's nothing to do with his injury. His recovery was good," he said.
"This season and also last season [he had a bad injury]. But I think he's very fine after the injury.
"It was a difficult injury, it was an injury that other players, other clubs, other medical assessments – they end in surgery.
"His option – with the medical opinions – was not to go to the surgery table and his recovery was really, really good.
"So I think he is more than fine in relation to his recovery from the injury which is an area sometimes where you have a recurrence. In his case, not at all."