Twenty-three goals were scored tonight in a record-setting, eyebrow-raising, and simply wild Champions League day across Europe.

Alex Oxlade-Chamberlain became the youngest Englishman to ever score in a Champions League game as he led Arsenal to a much needed 2-1 win over Olympiakos . APOEL Nicosia served notice that the Cypriots have to be taken seriously as they leapt atop Group G with a big road draw in Ukraine . And then there's Barcelona: They tore BATE Borisov apart in Belarus with a five-goal thrashing that made a mockery of UEFA's aims to "broaden" the biggest show in soccer.

Elsewhere, Zenit St. Petersburg topped Porto 3-1 in an early thriller marred by the sending off of Jorge Fucile; Bayer Leverkusen strolled to a 2-0 win over Belgians Racing Genk; Marseille dominated a stunned Borussia Dortmund 3-0 but took a late blow with the sending off of Jordan Ayew; and Chelsea's Salomon Kalou gifted Valencia a late penalty and a point in Spain.

Arsenal fans probably won't be fully convinced after tonight's win over Olympiacos, but they will gladly take the three points after a bizarre first half that saw as much promise up front as ineptness at the back. Oxlade-Chamberlain got the Gunners off to a bright start when 18-year old smartly took a long ball from Alex Song on the chest, then settled to fire neatly through three defenders. Defender Andre Santos added the second in the 20th when Tomas Rosicky fed him and defender Ivan Marcano was unable to clear it. It was indeed impressive stuff, especially from Rosicky who finally looked like the playmaker of old on the night.

Less appetizing -- at least for Arsenal's fans -- was their defending. The back line seems to find a way to hit new lows each week, and tonight really plumbed the depths. While Arsenal are missing two key men in Thomas Vermaelen and Laurent Koscielny, there was no excuse for the ball-watching and avoidance of man-marking that allowed David Fuster a header so free it was nearly criminal theft. Arsenal continued to wheeze and wobble and were lucky that Wojciech Szczesny was on his game and Mikel Arteta was there to clear a sure goal off the line.

The Gunners did settle down in the second half, and a visibly-tiring Greek side ultimately quit with about 20 to play, allowing Arsenal to move into second in Group F. They next face Marseille, which on the evidence, will be a tough tie.

Marseille powered past a bewildered Borussia Dortmund tonight, leaving manager Jurgen Klopp with some big questions. Andre Ayew opened the scoring in the 20th with a marvelous low scorcher from the left side after a superb cross from Loic Remy -- and the Germans had no answer. Key playmaker Mario Goetze was ineffective for long stretches of the night and it was not until Lucas Barrios pinged one off the bar in the final minutes that Dortmund looked capable of mounting a response.

Indeed, Dortmund seemed out-run and out-thought all game long as Ayew would go on to score another from the spot when he fed Remy in the box, only to see him cut down by Sebastian Kehl. Remy already had one of his own after Matt Hummels failed to cut out a searcher, allowing Remy to settle and fire home. The match was a relief for Marseille, who have struggled so far in Ligue 1, and further torment for the German champs, who have come out of the blocks badly in the Bundesliga. They next face Olympiacos at home, and now need a result.

Chelsea will rue three points tossed away, and manager Andre Villa-Boas will have some questions to answer. The Blues allowed Valencia a share of the spoils despite controlling this match for most of the night. Frank Lampard, who had endured both criticism and some groundless speculation coming into the match, showed himself to be, in fact, the consummate professional. His goal was the only shot to beat `keeper Diego Alves after the Valencia `keeper had put together a string of magical saves.

But Lampard didn't go the distance, and when he was subbed for Salomon Kalou with seven minutes remaining, the whole thing fell apart. Villas-Boas will surely be second guessed as Valencia pressed hard behind Roberto Soldado, finally getting a chance when Kalou obviously and needlessly handled the ball off a corner kick. Soldado stepped up to the spot, fired past Peter Cech and tied things up.

Chelsea next face Genk, a matchup they should relish. The Belgians were beaten and beaten well by Bayer Leverkusen in a game that was rarely in doubt. Lars Bender scored a beauty a half hour in with a long shot from the right flank that just nipped inside the far post. Former Chelsea man Michael Ballack added the capper in stoppage to condemn the Belgian makeweights to the floor of the group.

The shocker of the night was in Ukraine, where Shakhtar Donetsk were nearly floored by APOEL Nicosia in a game that was remarkable for how many chances the hosts missed. Goalkeeper Dionisios Chiotis stared down an alarming 26 shots on the night as Shakhtar's vaunted Brazilian line peppered APOEL's net. But Ivan Trickovski was able to latch on to a single long ball from Konstantinos Charalambidis to score -- on the Cypriot's second attempt goalward on the night. Jadson leveled things up three minutes later when the APOEL defense took a nap, but the damage was done -- and APOEL now sit top of Group G.

This will come as unwelcome news to Zenit St. Peterburg and Porto, who squared off in what was the best-played game of the day. James Rodriguez got the Portuguese champs on the board first when Hulk squared and settled a fine ball from Fernando Belluschi to capitalize on what had been a too-tentative early start from the Russians. There was a hint of offside on the goal but no denying the quality of the play.

But the Russians would awaken, with Portuguese import Danny pulling the strings and ultimately scoring the capper. Roman Shirokov was the hero on the night, first equalizing when Helton could not do better than parry a shot from Viktor Faizulin; then brilliantly knocking down Faizulin's free-kick and half-volleying the ball past the stunned Porto defense. Zenit were aided by the ejection of Fucile for two yellow cards in the first half but also showed a patience and craft that many thought they had possessed but not yet displayed.

The result was much-needed for the hosts and keeps the group wide-open. For Porto, it was their first loss ever on Russian soil, and just the second loss this year in European play. Their only previous defeat? To Barcelona in the Super Cup friendly this summer.

Speaking of the defending champions, Barcelona made mincemeat out of BATE tonight in a game that will be fodder for blooper reels to come. Hapless BATE conceded an own goal under heavy pressure as Alyaksandr Volodko beat one Lionel Messi to the ball. The Belarusians then had Alyaksandr Gutor totally gift Messi one when he dropped the ball at the little wizard's feet, allowing Messi to calmly finish into the open net.

Then there was the final goal. Someone really should tell the Belarusians that restarts should be passed to members of your own team, not David Villa. The striker was only too happy to accept the gift and bash home number five.

With the result, Messi became Barcelona's second all-time leading scorer and the youngest to boot. He is now just 41 goals shy of Cesar Rodriguez' mark of 235. If Barcelona were to play BATE every week, Messi could pass him within a month's time.

Finally, AC Milan took their time but finally wore down a Plzen side that was playing for a point, scoring thanks to a Zlatan Ibrahimovic penalty after Marek Cisnovski's handball in the 50th minute. Antonio Cassano settled things in the 66th when Ibrahimovic sent him in free and clear on Marek Cech's goal. He couldn't help but score.

Plzen's only spark came from Milan Petzrela, whose early header forced a fine stop from Christian Abbiati. But otherwise, Plzen's forays were high, wide, or snuffed out.