They have lost 10 of their 33 league matches this season and first-team coach Neville admits that they have not been good enough.
"We have not fulfilled any levels of expectations this season," he told BBC Sport. "We have failed on the football pitch and that doesn't sit kindly with anyone."
"We are not hiding away from the fact that we have underperformed. It's been difficult watching other teams above us do well and to even look at a league table.
"I find it difficult to watch Match of the Day on Saturday night; I find it almost impossible because we've suffered this season."
United are next in action when they face Everton at Goodison Park in the Premier League on Sunday.