(CNN) -- A 93rd minute Thiago Silva goal salvaged a late draw for AC Milan as they held Barcelona in their opening European Champions League Group H match on Tuesday.
It was the least Milan deserved after taking the game to the European champions, even going ahead within the first minute thanks to a piece of individual brilliance.
Brazilian international Pato slalomed through Barcelona's surprisingly porous defense before slotting home to give the home side an early, and unexpected, bloody nose.
Barcelona pressed for an inevitable equalizer with Lionel Messi again central.
After clipping the post a few minutes earlier, his mazy run found him enough space to stroke a ball across the penalty box that was gleefully tapped in by Pedro.
And when David Villa scored with a brilliant second half free kick, it looked like Barcelona would start their defense of the crown with an impressive win against one of the strongest teams in European football.
But Thiago Silva's late, late header shared the points.
Elsewhere in Europe goals were in short supply. It took Chelsea 72 minutes to break the deadlock against German side Bayer Leverkusen in Group E, Brazilian defender David Luiz curling in a right foot shot from Fernando Torres' lay off.
Spain international Torres was again the provider when he unselfishly squared the ball to compatriot Juan Mata with the match going into injury time, sealing a 2-0 victory.
Arsenal had their hopes of an early away victory against Borussia Dortmund in Group F dashed late on when an incredible Ivan Perisic volley cancelled out Robin van Persie's first half strike.
The result of the night, however, came from Cyprus where Apoel Nicosia came from a goal down against Russian champions Zenit St Petersburg with under 20 minutes left to win 2-1 in Group G.
Konstatin Zyryanov's second half strike looked to have sealed victory for Zenit, but two goals in three minutes from Apoel's Brazilian duo of Gustavo Manduca and Ailton turned the tie on its head.
Elsewhere in Group G Porto got their campaign off to a winning start by beating nine-man Shakhtar Donetsk 2-1 in Portugal. Striker Kleber made it a good night for Brazilians playing in Europe after scoring the winning goal in the second half.
Belgian side Genk fought a creditable 0-0 draw against Spain's Valencia in Group E, whilst Czech debutantes Viktoria Plzen also won their first ever Champions League point in Group H with a 1-1 home draw against BATE Borisov from Belarus.
In Group F Didier Deschamps' Marseilles got their Champions League challenge off to the best possible start against Greek side Olympiakos.
Argentina midfielder Lucho González' scored the only goal of a game that saw Olympiakos reduced to ten men after substitute Rod Fanni was shown a straight red card for a reckless challenge.