Tuesday saw the first half of Matchday 2 in the Champions League, with a number of enticing European encounters.
Arsenal played host to a dangerous Napoli side at the Emirates Stadium, while Chelsea were faced with a game which Jose Mourinho had been describing in "must-win" terms against Steaua Bucharest, having lost their opener to Basel.
Elsewhere, Celtic hosted Barcelona hoping for a repeat of last season's memorable home triumph—while Borussia Dortmund had the chance to get back on track in front of their home fans, with Marseille the opponents.
Click on for all the scores and analysis from Tuesday's eight matches.
Stats and quotes from UEFA.com unless otherwise stated.
Are Arsenal the real deal this season? Arsene Wenger's resurgent side put on a deeply impressive performance as they blew away Napoli 2-0 to take an early hold of Group F.
Mesut Ozil—with his first goal for the club—and Olivier Giroud (impressive throughout) grabbed two first-half strikes for the Gunners, as they blew away a side unbeaten this season in Serie A.
Rafa Benitez's side, without Gonzalo Higuain due to an injury sustained on Monday, improved in the second half, but Arsenal were never in serious danger of being hauled in.
The tone was set by Ozil, who showed exquisite timing and skill to score the first goal of the night with a controlled volley.
After playing a key role in that strike, Giroud then got on the scoresheet himself—firing home emphatically after the ever-aware Ozil found the Frenchman six yards out.
From that point until half-time Arsenal continued to dominate, splitting Napoli's defence seemingly at will—with Aaron Ramsey perhaps unlikely to continue his recent goalscoring run.
In the second half Napoli improved—they could hardly get worse—but were unable to get on the scoresheet, with goalkeeper Pepe Reina preventing his side suffering a worse defeat with a phenomenal save from Ozil.
There was no repeat of Rod Stewart's famous tears—or, if there was, it was for an entirely different reason—as Celtic lost to Barcelona thanks to a late goal.
Twelve months ago, at the same venue and against the same opposition, Celtic famously drove their famous rockstar fan to tears, as they beat Barcelona thanks to Tony Watt's finish. But a year on they suffered late heartbreak, as Cesc Fabregas headed home with ten minutes remaining to steal the points.
Prior to that, Scott Brown had been sent off in controversial circumstances following a clash with Neymar, who certainly seemed to make the most of whatever contact their was.
Barcelona, without the injured Lionel Messi, looked disjointed in attack throughout, with Neymar and Fabregas failing to link effectively. In the end it was Alexis Sanchez who would provide the winner, spotting his team-mate at the far post for Fabregas to take the headlines.
Much focus will still be on Neymar, however, as he was involved in the incident that saw Brown dismissed. Brown was guilty of a cynical foul on the Brazilian as he ran through on goal, but seemed to be sent off for running into his opponent afterwards—with Neymar writhing around in agony despite replays showing he was hardly touched.
Despite the controversy Barcelona felt they warranted the win; they enjoyed 72 per cent of possession and had 13 shots to the home side's four.
A dramatic conclusion at the Amsterdam Arena ended with Mario Balotelli converting from the penalty spot to give his side a point, moments after defender Stefano Denswil thought he had won it for the home side.
Denswil, a 20-year-old academy graduate, headed home from an 89th minute corner to give his side a late lead, but minutes later Mike van der Hoorn brought down Balotelli to give the Italians a late chance at redemption.
Balotelli, who missed the first penalty of his professional career earlier this season, made no mistake—making a "silence" gesture to the partisan crowd.
Milan were far from impressive for much of the contest and were perhaps lucky to get a point—with Ajax enjoying 70 per cent of possession over the contest.
Reigning runners-up Borussia Dortmund got their Champions League campaign back on track with a comfortable 3-0 win over Marseille on Tuesday.
Dortmund, looking to rebound after a somewhat abject opening defeat to Napoli in Naples, utterly outclassed Marseille throughout—with Robert Lewandowski scoring twice and Marco Reus grabbing a fortunate other to leave Group F already looking like the tight three-horse race many predicted.
Lewandowski got the first and last goals; the first as he tapped in a fine team move, the second from the penalty spot.
In between, Marco Reus saw a floated 45-yard free-kick evade everyone and beat Marseille goalkeeper Steve Mandanda, rounding out a win that will have pleased manager Jurgen Klopp, who was banned from the touchline after letting his anger get the better of him in the game against Napoli.
Dortmund actually had less possession than Marseille, but dominated them in chances created—firing 18 to Marseille's seven.
Andre Schurrle was impressive throughout as Chelsea got the emphatic victory manager Jose Mourinho demanded to kick-start their European campaign.
Demanding a response following the home defeat to Basel on Matchday 1, Mourinho saw his side rip Steaua apart at will—with Ramires (twice), Frank Lampard and an own goal completing a comfortable 4-0 win.
Schurrle tore past his opponent, right-back Daniel Georgievski, at will all game—with the unfortunate youngster scoring his side's own goal (unable to get out of the way after Samuel Eto'o's strike was parried into his path) in a performance to forget.
Ramires scored two goals—the second particularly emphatic—but Chelsea's night was soured somewhat by an injury to Fernando Torres, who was forced off in the first half to be replaced by Eto'o.
Julian Draxler's exquisite volley—arguably the goal of the night—was the difference as Schalke defeated Basel on Tuesday, in a game overshadowed by a protest that briefly delayed the first half.
Draxler hit a first-time effort from the edge of the box to win the game for his side, but not until after Greenpeace protesters had disrupted the game by abseiling from the roof at St. Jakob Park—protesting against some of the actions of competition (and Schalke) sponsors Gazprom.
Basel vs Schalke is temporarily halted, as protesters abseil from the stadium roof. pic.twitter.com/GlXSZoolaK— Football Away Days (@awaydays_) October 1, 2013
On the pitch though it was Draxler who added to his burgeoning reputation, as Schalke moved top of Group E as the only unbeaten team.
A late finish from Arda Turan after a well-worked free-kick enabled a below-par Atletico Madrid to continue their great start to the season with a 2-1 win against Porto.
Jackson Martinez, the Colombia international, had given the home side a lead inside the first 15 minutes, but strikes from Diego Godin (from a corner) and Turan completed the turnaround for Diego Simeone's men.
Turan's goal was particularly clever, the Turkish attacker slipping in behind the wall to collect Gabi's laid-off free-kick, before turning a lashing over the goalkeeper and into the net.
Porto dominated possession (59 per cent) and had more shots (14 to 11), but were undone by their organisation in crucial situations.
Finally, in the day's early kick-off Zenit St. Petersburg and Austria Wien played out a 0-0 draw.
Zenit were hurt by Axel Witsel's first-half dismissal—one that replays suggested was somewhat unfair—but neither side really looked like breaking the deadlock in a dull affair.
The match saw 34 attempts on goal (18 for Wien) but just 16 on target, as the goalkeepers ensured both sides shared the spoils—getting them off the mark in Group G.