The City boss has admitted his illustrious career to date does not include such a sizeable comeback, and he might be tempted to force the pace from the first whistle. But Mancini feels that would be a mistake and given City's generally impressive home form, they should stick to a usual game-plan.
"We must be patient," said the Italian. "I have never come back from 2-0 down and I know it is going to be very difficult because it was such a bad result. But that is why it is so important to play our normal game and not try to achieve the result in the first 45 minutes. If we do that, at the end of the match we will see if we have won."
Given the number of times Mancini has spoken about the tiredness in his squad, he might even be relieved if City tumbled out this evening, even though it would end one of their two remaining hopes of silverware this term.
The return of James Milner from a hamstring injury at least offers some respite from the injury nightmare that has engulfed the Blues, with Mancini denying he has been the architect of his own downfall by allowing Emmanuel Adebayor, Wayne Bridge and Roque Santa Cruz to leave on loan in addition to three of his younger players.
"If there are some players who want to leave because they wish to play every game, it is difficult," he said. "Should two or three players leave the club, you could buy two or three more. But we didn't think four or five important players would get injured in the space of 20 days."
Shay Given, James Milner and Adam Johnson have all been sidelined for extended periods, with a succession of minor injuries to be taken into account as well.
In addition, Kolo Toure is suspended indefinitely pending an inquiry into his failed drugs test, robbing Mancini of another valuable option.
"When you become a top club you should have 25 players available in every game," he said.
"If you watched the game between Manchester United and Arsenal in the FA Cup, United changed eight players. When you play every three days, you need to change five or six players, minimum."