Sports Mole takes a look at the key factors from the contest inside the Amsterdam ArenA.
Shots on target: 6
Shots on target: 6
Was the result fair?
Man City have not defended well enough in the Champions League this season and that was their problem once again tonight. Ajax controlled the match for long periods despite the early goal from Nasri and deserved the three points.
Frank de Boer will be overjoyed with his team following their first win against an English club on home soil since 1980. The home side's quality on the ball has been well documented but the youthful Dutch champions showed the maturity to play patiently to keep their hopes of progress alive.
Man City's performance
The visitors were weak in defence with little to offer in attack. Mancini will be left with more problems to solve following a third disappointing performance in the competition. City threatened to take control of the game following the break but three lapses of concentration condemned the Premier League champions to defeat.
Sports Mole's man of the match
Siem de Jong has been touted as a future star of the European game and the 23-year-old stood out for De Boer's side inside the Amsterdam ArenA. The club captain dominated the midfield, keeping Yaya Toure quiet and it was his performance, alongside Christian Eriksen's, that provided the platform for the famous victory.
Oddvar Moen was impressive during the contest. His willingness to allow the game to flow was obvious throughout and he was able to keep the match under control when some City players started to show their frustration.
The two sides meet once again in a fortnight at the Etihad Stadium. Although qualification for City is still possible, anything less than a victory in the reverse fixture will spell the end for Mancini's men in the Champions League. Ajax will head to Eastlands full of confidence and De Boer's men will be hoping to build on their impressive display on Wednesday.