The champions of England were shambolic defensively and lacking discipline as they succumbed to their clever, quick-moving and obdurate Russian visitors.
Manchester City can rail all they like against a poor referee but they were culpable for both of Seydou Doumbia's goals and there could be little sympathy over the two dismissals, for Fernandinho for two yellows, and a straight red for goalscorer Yaya Toure for violent conduct.
Manuel Pellegrini was brought in to build City into a European force but they are now bottom of Group E, needing to win against Bayern Munich and Roma to progress to the knock-out stage, also relying on other results.
City are 10 points behind leaders Bayern after four games. This was not what Abu Dhabi ordered.
They now face a huge battle to qualify and will be depleted. If City will not see Toure for three European games for violent conduct, it will be interesting to see when Tasos Sidiropoulos next features in the Champions League. The referee mistakenly booked Sergei Ignashevich for a foul on Sergio Aguero when the offence was by Pontus Wernbloom, who was already on a booking following a disgraceful challenge on Toure in the first half.
Sidiropoulos also denied Aguero a late penalty appeal when the Argentinian was clearly fouled. Beware Greeks bearing gaffes.
If hardly in the league of Tom Henning Ovrebro's incompetence at Stamford Bridge in 2009, it was not a good performance by Sidiropoulos, who was surrounded by Samir Nasri, Pablo Zabaleta and Aguero at the end, with Vincent Kompany and Joe Hart soon joining the protest.
The cold war had begun early with fans of the English hosts demanding that police and stewards remove Russian interlopers. CSKA fans were banned from attending following racist incidents in Moscow but some managed to infiltrate the home gathering, revealing themselves when celebrating CSKA's first-half goals and eventually being rounded up and led away.
Pellegrini had called on his players to show greater concentration, avoiding defensive lapses, but they failed to mark with sufficient rigour early on, gifting CSKA the lead after only two minutes. When Gael Clichy gave away a cheap free-kick which Bebras Natcho curled over from the right, Doumbia escaped from the slumbering Toure and headed powerfully past Joe Hart.
It was shocking defending by City, who were totally caught cold. So were the Etihad stewards who needed guidance from City fans to locate the knots of celebrating Muscovites.
City needed inspiring. Their midfield balance was not right, being too open again, and not giving sufficient protection to their back-line, leading to Pellegrini's changes at the interval, trying to make his side more compact with the arrival of Fernandinho and Nasri.
Until then Jesus Navas and Stefan Jovetic had failed to have much of an impact, barring Jovetic's run after eight minutes which was illegally curtailed on the edge of the Russians' box. Toure took responsibility, making up for his earlier error with a lovely free-kick looping over the wall and beating Igor Akinfeev.
It should have been the moment for City to build momentum while being aware of CSKA's threat on the counter with the likes of Doumbia and Ahmed Musa speeding through. When Martin Demichelis slipped, Doumbia had a free run on goal and should have scored but placed his shot wide.
City were looking again to Toure for hope. The visitors knew this and Wernbloom went in on the City midfielder with a body-check of such ferocity that it sent Toure tumbling through the air. It could easily have been red, and Toure was fortunate to escape injury, but the referee decreed it worth only a yellow.
It was the excellent counter-attacking Russians who struck next. After 33 minutes, Clichy erred badly in giving the ball away seconds before Doumbia slammed the ball past Hart.
Pellegrini made his double change at the break, bringing Fernandinho into midfield to assist Fernando for a while. Navas' exit brought Nasri on to the left with James Milner switching right. Milner still got forward and was denied by the superb Akinfeev.
City went down to 10 men after 70 minutes. Fernandinho had just been cautioned for a foul on Alan Dzagoev and was now punished for impeding Musa. The mood was now a mix of dissent and defiance. City fans applauded Fernandinho as he walked, then ran off. They railed at the referee, at Uefa.
They had brief hope when Dzeko darted through, running on to a pass from Aguero, but Akinfeev saved. The CSKA keeper then clutched a Toure free-kick. That resulted from a Wernbloom foul on Aguero yet it was Ignashevich, booked who was cautioned. City fans were enraged. Kompany ran 50 yards to make a point but to no avail.
City lost their discipline. Toure then was then dismissed for a straight red for raising his hands to Roman Eremenko. Aguero was cautioned for an apparent dive and was upended again minutes later but Sidiropoulos waved play on.
It was a night from which City will do well to get back off the floor (© Daily Telegraph, London)