PARIS - European football's big reputations counted for nothing on Wednesday as Real Madrid, AC Milan, Manchester City and Arsenal all lost in the Champions League, while Paris Saint-Germain cruised to a comfortable 2-0 win at Dinamo Zagreb.
Nine-time European champion Real Madrid lost 2-1 at Borussia Dortmund; seven-time champion Milan's woeful season continued with a 1-0 loss at Malaga, while City blew a 1-0 lead on the way to a 3-1 defeat at Ajax, and Arsenal was humbled by a 2-0 home loss to German club Schalke.
"I prepared the players badly for this game," City manager Roberto Mancini said. "This defeat is my fault."
The day after Manchester United scraped a 3-2 win at home to Braga, the erratic form of Premier League teams was again thrust into the spotlight with City conceding sloppy goals and Arsenal's misfiring forwards being given a lesson in clinical finishing by Schalke.
Madrid defended in numbers but fell behind to Robert Lewandowski's goal late in the first half, but the lead lasted barely a minute with Cristiano Ronaldo equalising from a deft lob.
Defender Marcel Schmelzer scored Dortmund's winner to extend Madrid's terrible record in Germany. The Spanish side has now lost 17 of 24 games in Germany against a German opponent - and the only win was a 3-2 victory at Bayer Leverkusen in 2000.
"It's a sensational evening, such as you can only imagine in your wildest dreams," Dortmund coach Juergen Klopp said.
Dortmund tops Group D with seven points, one more than Madrid. Ajax has three points, while City has one and is in real danger of a second consecutive group-stage exit.
Midfielder Samir Nasri gave City the lead after being set up by James Milner, but Ajax hit back with goals from striker Siem de Jong, defender Niklas Moisander and silky midfielder Christian Eriksen.
Milan, which lost its past two Serie A matches to drop to 15th place in the standings, got one reprieve but not a second as Joaquin Sanchez made up for a penalty miss by scoring the second-half winner for Malaga. The Spanish side is in control of Group C with nine points.
"Nobody imagined this. We didn't know what would happen each morning and look at what's happening now," Joaquin said. "I think all of Malaga made history today. Milan's not in its best moment but it's still a top club."
Milan is still in a decent position to qualify as it has four points, one more than Zenit St. Petersburg, which beat Anderlecht 1-0 at home thanks to Alexander Kerzhakov's second-half penalty — his 200th career goal. Anderlecht is last with one point.