Malaga and Porto remain flawless in the 2012 UEFA Champions League after home wins on Wednesday over Milan and Dynamo Kiev, but Manchester City sealed an early exit with an embarrassing away loss to Ajax Amsterdam.

Real Madrid fell 2-1 to Borussia Dortmund in Germany and Arsenal suffered a 2-0 defeat by Schalke 04 in front of the faithful at Emirates stadium in London.

Zenit St. Petersburg topped visiting Anderlecht 1-0, while host Dinamo Zagreb lost 2-0 to Paris St Germain.

Home field advantage was also not enough for Montpellier HSC, which lost 2-1 to Olympiakos Piraeus.

Joaquin's goal in the 64th minute gave Malaga a 1-0 triumph over mighty AC Milan and left the Spanish club with nine out of nine possible points in Group C and an excellent chance of advancing in its first appearance in the Champions League.

Porto, meanwhile, needed Jackson Martinez's goal in the 78th minute to edge Dynamo Kiev 3-2 and bring its point total to nine, three ahead of Paris Saint Germain in Group A.

Borussia Dortmund grabbed a one-point lead in Group D with a 2-1 victory over Real Madrid.

The German side struck first, with a tally in the 36th minute by Robert Lewandowski, but Cristian Ronaldo evened the score two minutes later. The visitors, however, were unable to get the equalizer after Marcel Schmelzer put the home side ahead in the 64th minute.

Manchester City, which came into Wednesday's match in desperate need of a win, took an early lead in Amsterdam on Samir Nasri's marker in the 22nd minute, only to give up three unanswered goals.

The defending Premier League champions have earned only a single point in the group round.

The other English club in action on Wednesday, Arsenal, was shut out and gave up two late goals to Schalke 04, who now lead Group B with seven points, one more than the Gunners. EFE