Dzeko is feeling his way at Eastlands after arriving in the January transfer window from Wolfsburg for a reported £24million. The Bosnian's only goals so far have come in cup competitions and he could return to the team in the Europa League last-16, first leg meeting with Dynamo Kiev on Thursday after Carlos Tevez and Mario Balotelli started against Wigan at the weekend.
He said: "These three strikers (Dzeko, can play together sometimes but not always. When they do it's important that they work. As for Edin it is not easy to start with a new team in a new league in January, but I believe he will become one of the best strikers in England."
City trained at Carrington rather than in Kiev, where temperatures have dipped to below freezing with the remnants of snow littering the city.
Mancini said: "It will be a difficult game but it's only the first half. I hope we can play a good game, score a goal and win if possible.
"We have good players and a good squad. I don't know what kind of football we can play. The problem is the pitch. It's so hard because it's cold at the moment."
Shaun Wright-Phillips could come into contention after missing two games with a back problem.
Nigel de Jong, who has recovered from an ankle injury, is pushing for his first start in over a month.
James Milner is absent with a hamstring strain while Kolo Toure is banned indefinitely after failing a drugs test.
Mancini added: "Kolo is a serious professional player. We said one week ago that we want to win games for him."