Cristiano Ronaldo scored the winner in the 90th minute as Real Madrid defeated Manchester City 3-2 at the Santiago Bernabeu.
All five goals came in an incredible final 20 minutes of the second half in which City twice were in front.
Edin Dzeko came off the bench to give the visitors the lead after 69 minutes following a surging run from midfield from Yaya Toure, but Marcelo quickly replied with a curling shot.
The home supporters were left stunned when Aleksandar Kolarov’s free-kick drifted untouched into the bottom corner of Iker Casillas’ goal but Karim Benzema again pulled Madrid back with a sublime turn and finish.
And Ronaldo ensured that Jose Mourinho’s team put their early season woes behind them with a dipping shot that flew past both Vincent Kompany and Joe Hart.
Ronaldo tested City early and Hart was called into action again when Gonzalo Higuain deflected a powerful shot with his head from close range.
Two adventurous midfield runs by Toure began with promise but ended without troubling Casillas and Higuain went close again when he latched on to Di Maria’s cross to the back post before the half was out.
Mancini had already introduced Kolarov from the bench when Samir Nasri suffered a hamstring injury in the first half and with both benches littered with attacking talent, more changes seemed inevitable.
Dzeko was next to take the field, replacing David Silva, and the Bosnian would provide the cutting edge that had been missing.
Toure, who had looked City’s biggest threat all night long, broke out of the midfield again to create a two-on-one attack and this time successfully found his target with a simple through ball. Dzeko took the pass in his stride and beat Casillas with a composed, low left-footed finish.
The Spanish champions immediately looked more dangerous in the final third following the changes, though, and Marcelo curled a right-footed shot into the top corner after shaking off Kompany just outside the penalty area.
Set-pieces have troubled Madrid all season and after Pablo Zabaleta had failed to get contact on Carlos Tevez’s low cross, Kolarov delivered a free-kick that found its way into the back of the net.
Incredibly, though, there was more to come, and Roberto Mancini’s celebrations on the sideline were short-lived. Benzema was next to strike after a mazy run from Di Maria, turning on the edge of the box and firing a powerful, low shot into the bottom corner.
And City’s hearts were broken when Ronaldo stepped inside Zabaleta – who had relieved Maicon of his duties of marking the Portugal star – and released a dipping shot that beat the partially obscured Hart after Kompany had put himself in the way of the ball but failed to head clear.
Meanwhile, Robert Lewandowski’s goal three minutes from time earned Borussia Dortmund the points in a 1-0 home win over Ajax.
Lewandowski collected a high ball from the right, evaded Toby Alderweireld’s tackle, and fired home from close range.