Mancini's options have been limited due to the shoulder injury sustained by Shay Given that will rule him out for almost all the remainder of the season. Last season City ended up ended up bringing in Marton Fulop on an emergency loan after failing to recall Hart from a loan spell at Birmingham when Given got injured.
"Last year we were unlucky. It is impossible that we will be unlucky like that again," said Mancini.
"Joe is young. I hope he will be strong and can play all the games until the end. I am not going to try and loan someone."
It is just a measure of the fitness problems Mancini is trying to combat ahead of Sunday's Premier League encounter with Fulham at Eastlands. City are already without half a dozen senior men and Vincent Kompany may join them after sustaining a hip injury against Aris Thessalonika in midweek.
Should City draw their FA Cup fifth-round tie with Aston Villa on Wednesday, the replay has been scheduled for Monday, March 7, two days after the Blues tackle Wigan in the Premier League at Eastlands and only three before a punishing round trip to Kiev of 4,500km for the Europa League first-leg tie with Dynamo.
It is fixture congestion the likes of which Mancini has never encountered before. And the Italian does not believe it is fair.
"In my life I have never seen that a team arrives in February and March and has to play every two days," he said.
"This is a big problem, not only for us but for all the teams. Something should change because this is impossible for all English players.
"At every World Cup and European Championships, there is a problem for England because all their players are tired. We should have more respect for them. They are not machines."