Midfielder Fernandinho believes what has happened to Hart - hailed as the world''s best just a year ago - is a strong reminder of the high standards demanded at Eastlands.
Fernandinho: "If the quality is a bit off you must work harder to recover your position and your best quality.
"If he at the moment is not (at his best), he must work more hard.
"But they are very good keepers, he and Pantilimon. I think his career will be better for it.
"The manager must choose the best team, and the best keeper for the team.
"I am sure if he played Joe Hart or Costel Pantilimon the team would be superb because they are both very good goalkeepers."