Tuesday saw the first half of Matchday 3 in this year's Champions League, an often pivotal phase of the group stages of the competition.
In London, Arsenal were hosting Borussia Dortmund—knowing that victory would put them within touching distance of the knockout phase, but defeat would leave them facing an arduous path to that goal.
Chelsea, similarly, knew they could ill afford defeat against Schalke after their opening-round disaster against Basel—while the undoubted glamour tie of the night saw Barcelona visit famous old rivals AC Milan.
Five other games were also being played around Europe, with much at stake for every side.
So click on to read about events from all eight of Tuesday night's matches.
(Statistics via WhoScored?, quotes via UEFA.com, GIFs B/R own unless otherwise stated)
A late volley from Robert Lewandowski condemned Arsenal to a first defeat of this year's Champions League group stage—but Arsene Wenger's side now face three difficult games if they are to progress to the knockout stages.
Wenger, on his 64th birthday, saw his side impress after Henrikh Mkhitaryan's somewhat fortuitous opener, with Olivier Giroud getting a deserved equaliser. Substitute Santi Cazorla then hit the crossbar with a wonderful effort, before Lewandowski stole all three points with a clinical finish from Kevin Grosskreutz's pinpoint cross.
Lewandowski arguably should not even have been on the pitch, however, having been guilty of an ugly elbow on Laurent Koscielny only minutes earlier. In the end, however, the Polish striker received only a yellow card.
Wenger, too, might be somewhat disappointed at the manner of the opening goal—Aaron Ramsey guilty of giving the ball away on the edge of the box, as Lewandowski slipped the ball to Mkhitaryan to swipe an effort beyond Szczesny.
Giroud's equaliser was a product of a fantastic cross from Bacary Sagna, but further incisive play was not forthcoming, as Lewandowski eventually got the crucial goal.
Arsenal now sit on six points, the same as Dortmund and Napoli, with both those sides still to visit.
"It's going to be tough now," Mikel Arteta said afterwards. "This is probably the toughest group in the competition but I think we are still capable of going through."
Shots on Target: 2-3
Pass completion: 83%-79%
While Arsenal were seeing their Champions League fortunes take a turn for the worse, Chelsea look to have a straightforward path to the next round after demolishing Schalke, 3-0, in Gelsenkirchen on Tuesday.
With a home meeting with Schalke next up, the Blues are level with the Bundesliga club at the top of the standings on six points after three games, a rapid turnaround after the opening matchday defeat to Basel at Stamford Bridge.
The win was not as comfortable as the scoreline may suggest, however, with Petr Cech making a number of impressive saves in the period between Torres' fourth-minute opener and his second with 20 minutes remaining.
"We were lucky to score the first goal early," Torres noted. "In the second half, the individual quality made the difference. To get the last six points away from home is very important."
Fernando Torres has 8 goals in 22 UCL games with Chelsea. He had 8 goals in 21 UCL games with Liverpool.— Paul Carr (@PCarrESPN) October 22, 2013
Shots on Target: 5-4
Pass completion: 90%-84%
The most glamorous tie of the night ended in a draw, as Barcelona and AC Milan both appeared content to share the spoils in a 1-1 contest at the San Siro.
Robinho, formally of Real Madrid, scored the opener—enjoying a nice exchange with Kaka before slipping the ball home. But Lionel Messi once again bailed his side out with the equaliser, before both sides turned down the tempo as the contest wore on.
The shared point keeps Barca top of Group H with seven points, with Milan in second two points behind. Milan manager Max Allegri noted afterwards:
Shots on Target: 2-6
Pass completion: 75%-91%
Arguably the goal of the night from substitute Duvan Zapata sealed the points as Napoli beat Marseille, 2-1, to make things tight at the top of Group F.
Jose Maria Callejon opened the scoring with a fine goal of his own shortly before halftime to set Rafa Benitez's side on their way against a dour Marseille side, before Zapata—after a great assist from the lively Dries Mertens—came on and thundered home a beautiful strike to seemingly seal the points.
But Andre Ayew scored a fine dipping strike to give his side hope, as the Serie A side were eventually forced to scramble to preserve the victory.
They now remain level with Dortmund and Arsenal on six points, with a home game against the Premier League side (and Marseille) still to come.
Afterwards, Benitez noted:
Shots on Target: 2-4
Pass completion: 82%-80%
Elsewhere in Group H, it is Celtic who can continue with dreams of progressing from a difficult group after they picked up a hard-fought 2-1 victory over Celtic.
James Forrest—from the penalty spot—and Beram Kayal grabbed the crucial goals for Neil Lennon's side, with Lasse Schone's finish for Ajax only coming with moments remaining in the contest.
Prior to that, Celtic saw substitute Nir Biton sent off for a late challenge.
In truth the crucial moments in the contest came in the second half. Forrest put Celtic ahead after Stefano Denswil had tripped Anthony Stokes down the left, but in the second half Ajax returned determined.
Fraser Forster made a critical save and then moments later Celtic were two clear, Kayal's tame shot being deflected beyond the wrong-footed goalkeeper.
Shots on Target: 4-4
Pass completion: 80%-87%
At the top of Group G sit Atletico Madrid, who look odds-on for the knockout stages after their 3-0 win over Austria Wien extended their unbeaten record.
Raul Garcia tapped in the away side's opener, before Diego Costa produced two clinical finishes to wrap up the points for Diego Simeone's side. It was a fine way for the Brazilian to make his debut in the competition.
Shots on Target: 1-6
Pass completion: 85%-82%
Alexander Kerzhakov's solitary strike four minutes from time was enough for a poor Zenit St. Petersburg to steal all three points against a shocked Porto side.
Porto's job was complicated by the sixth-minute dismissal of defender Hector Herrera, who was booked for a foul before receiving his marching orders seconds later after encroaching on the subsequent free-kick.
Yet, despite that setback, Porto continued to dominate—before Kerzhakov popped up with a sucker-punch that leap-frogged the Russian side above their opponents to second in Group G.
Porto midfielder Fernando said afterwards:
Shots on Target: 5-5
Pass completion: 76%-85%
Finally, a late finish from Leandro Tatu saw Steaua Bucharest claim their first point of this year's Champions League with a 1-1 draw against Basel in Romania.
Marcelo Diaz had opened the scoring for the Swiss side with a beautiful curler—punishing an error from the Steaua defence—but the home side were never killed off, and made the most of that glimmer of hope when Tatu arrived on time in the box to turn home with four minutes remaining.
Steaua nevertheless remain bottom of Group E with one solitary point, with Basel dropping to third on four points—two adrift of Chelsea and Schalke.
Shots on Target: 6-4
Pass completion: 74%-81%