Real Madrid scored twice late in an electrifying finish to beat Manchester City 3-2 to open the Champions League group stage, while Paris Saint-Germain marked its new big-spending era with an emphatic 4-1 win over Dynamo Kyiv on Tuesday.
Madrid forward Cristiano Ronaldo beat goalkeeper Joe Hart in the 90th minute to cap a dramatic comeback as the Spanish champions twice came from behind for a moraleboosting victory over the English champions following a week of domestic disarray.
While Madrid showed its pedigree as nine-time champion against its rich and ambitious opponent, AC Milan's comparable history in European competition couldn't help it shake off its early season troubles as it was held to a 0-0 draw at home by Anderlecht.
Also, Robert Lewandowski scored late as Borussia Dortmund kept pace with Madrid in the tough Group D with a 1-0 win over Ajax.
Arsenal shook off its poor away form in the competition to win 2-1 at French champion Montpellier, while Schalke also opened Group A with a 2-1 road win at Olympiakos.
FC Porto won 2-0 at Dinamo Zagreb, while Malaga thrashed Zenit St. Petersburg 3-0 in its competition debut.
City hoped to get off on the right foot after missing out on the knockout stages last season. The big-spending Premier League club certainly had its chance only to come undone against a dogged opponent desperate for a victory to put its recent glum form behind it.
"The most important thing was to win and we did that. The team is good, the fans are good and I'm good," said Ronaldo, who returned to the Santiago Bernabeu for the first time since saying he felt "sad" at the club. "It was a crazy game."
City had done well to soak up Madrid's pressure in the first half before twice taking the lead in the second.
"It is difficult not because we lost - we can lose against a side like Real Madrid - but because with four minutes to go it was 2-1," City manager Roberto Mancini said.
Madrid's weakness on set pieces again proved costly as Aleksandar Kolarov curled home a free kick in the 85th minute to re-establish the visitors' advantage after Marcelo had cancelled out Edin Dzeko's 68th-minute opener.
Madrid came roaring back, however, as substitute Karim Benzema squeezed home an 87thminute equalizer past Hart, before Ronaldo capped the comeback as the hosts responded to strong criticism from its coach and fans regarding its poor start to the domestic season.
Ronaldo, who refused to celebrate when scoring in his last home game, didn't hesitate to do so this time and neither did coach Jose Mourinho.
"I recovered my team, now I just hope I don't lose it," Mourinho said.
