Mancini's options have been limited due to the shoulder injury sustained by Shay Given that will rule the Irishman out for almost all the remainder of the season.
It means City only have Stuart Taylor as back-up and he has not played a first-team game for 13 months, an FA Cup tie at Scunthorpe.
For City, the spectre of last season's nightmare, when they 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 during the latter weeks of the campaign, is looming again.
But Mancini will resist a panic move, trusting to Hart's fitness to fate.
"Last year we were unlucky. It is impossible that we will be unlucky like that again," said the Italian. "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."