The Premier League winners are without a win in Europe this season after an opening loss to Real Madrid before rescuing a 1-1 draw with Borussia Dortmund.
Mancini is braced for a tough test against Ajax but the Italian acknowledged that nothing less than a victory will suffice at the Amsterdam Arena.
“We can’t think about not winning before the game,” Mancini said. “We have to think about winning this game.
“People think it will be easy but Ajax have a good young team and will play well. It will be a difficult game.”
Mancini also conceded City’s inexperience in the competition could be partly to blame for a disappointing start, but the Italian also feels his side were unfortunate to be drawn in such a tough group.
“Maybe as a club we need more experience, but we have good players and that’s why we should be in the second stage,” Mancini added.
“It is not easy because you need luck in this competition when you have the draw for the group.
“We want to play for a better seeding. We started the group so-so, but we still have a chance to go through – but we must take our chance.”
• Already beaten by Borussia Dortmund and Real Madrid, bottom-placed Ajax are seeking a first home victory over English opposition since 1980, when they beat Nottingham Forest 1-0 in the second leg of the 1979-80 European Champion Clubs’ Cup semi-finals.
• City’s only previous trip to the Netherlands yielded a 1-1 draw at Twente in the 1978-79 Uefa Cup first round. They beat Twente 3-2 in the ensuing home leg and won by the same score when the clubs met again in the 2008-09 Uefa Cup group stage.
• City failed to reach the knockout stages last season despite collecting ten points in the group stage, matching the record for the highest points haul without advancing.
• Ajax coach Frank de Boer made his international debut in September 1990 in the Netherlands’ 1-0 defeat in Palermo against an Italy side for whom Roberto Mancini, his City counterpart, appeared as a 55th-minute substitute.
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