Match ends, Swansea City 0, Arsenal 3.
Arsenal kept up the pressure on Premier League leaders Manchester City with a ruthless second-half dismantling of Swansea City.
Swansea's Bafetimbi Gomis squandered the best chance of an entertaining but goalless first half.
Olivier Giroud headed Arsenal in front soon after the restart, before Laurent Koscielny seized on an error by former Gunners goalkeeper Lukasz Fabianski to double their lead.
Joel Campbell struck on his first Premier League start to seal victory and keep Arsenal, missing several key players because of injury, level on points with Manchester City, who have a superior goal difference.
For Swansea, the result is a setback after ending a six-game winless run against Aston Villa in their previous outing.
Arsenal title contenders?
Having had to withstand concerted Swansea pressure in the first half, Arsenal were transformed after the interval as they strolled to a convincing victory.
They had failed to win any of their previous three meetings with the Swans, but Arsene Wenger's side produced a clinical second 45 minutes which suggested they could sustain a serious title challenge.
France international Giroud made the breakthrough with his fifth goal in six games for club and country, nodding in unmarked from Mesut Ozil's corner to score the 2,000th goal of Wenger's Arsenal tenure.
If Swansea's defending was slack on that occasion, it was found wanting again as Fabianski spilled a looping ball into the path of Koscielny, who had the simple task of tapping into an empty net.
Gunners coping with casualties
Arsenal's second-half stroll was particularly impressive considering Alex Oxlade-Chamberlain and Theo Walcott were added to their growing injury list during Tuesday's abject 3-0 League Cup defeat by Championship side Sheffield Wednesday.
The shock of that loss was particularly jolting, coming as it did after victories over Everton and Bayern Munich.
But the pain of defeat was perhaps less severe than the headache caused by those injuries, with Aaron Ramsey, Mikel Arteta, David Ospina, Jack Wilshere, Danny Welbeck and Tomas Rosicky already out.
Their absence paved the way for Campbell's first Premier League start, and the Costa Rican took his opportunity as he fired in firmly from Ozil's cross to add a final gloss to Arsenal's victory.
Goalless Gomis a worry for Swansea
Gomis scored the winner on both occasions as Swansea did the double over Arsenal last season - but he is currently in the midst of a barren spell.
The Fance international striker had failed to score in his previous six Premier League appearances, and his loss of confidence was evident as he missed a glorious opportunity midway through the first half.
Clean through after an incisive through ball from Jonjo Shelvey, Gomis hesitantly took the ball around Petr Cech and fell under the pressure of the goalkeeper's sliding challenge, appealing in vain for a penalty as Hector Bellerin cleared.
Man of the match - Mesut Ozil
What they said
Swansea City manager Garry Monk: "There were a lot of positives in our play and we were exceptional in the first half. We should have taken the lead when we were on top.
"We gifted them two goals and you can't do that against any team, let alone Arsenal. I'm disappointed to lose, but I think the scoreline flatters Arsenal."
Arsenal manager Arsene Wenger: "Swansea took six points off us last year and that shows we've moved forward. The second half we were a different team.
"After we scored the first goal, it was all us and there was only one winner on the pitch. Joel Campbell took his goal really well and he is still a young player who had to wait for his chance.
"He's adapted to Europe, been in a few leagues and come back and I like his team spirit and work rate."
Arsenal will not have much time to celebrate this result ahead of a huge week for them. They travel to Germany for Tuesday's crucial Champions League game at Bayern Munich, then host Tottenham Hotspur in the north London derby at Emirates Stadium on 8 November.
Swansea will hope to get back to winning way when they face Norwich City at Carrow Road in the Premier League on 7 November.
The stats you need to know
- Since making his Premier League debut in August 2012, Olivier Giroud has scored more headed goals than any other player (15).
- Swansea are now without a win in four home league games (D2 L2); their worst run under current boss Garry Monk.
- Mesut Ozil has made more assists (22) than any other Premier League player since his debut in September 2013.
- Laurent Koscielny has scored in back-to-back games for the first time in his Arsenal career.
- Swansea failed to score in consecutive home Premier League games for the first time since May 2013.
- 6WilliamsBooked at 89mins
- 4Ki Sung-yuengBooked at 57minsSubstituted forBrittonat 85'minutes
- 10A Ayew
- 23G Sigurdsson
- 20MonteroSubstituted forBarrowat 79'minutes
- 18GomisSubstituted forMacedo Lopesat 85'minutes
- 17Macedo Lopes
- 28CampbellSubstituted forGibbsat 84'minutes
- 11ÖzilSubstituted forIwobiat 90+3'minutes
- 12GiroudSubstituted forChambersat 84'minutes
- Kevin Friend
- Shots on Target
Second Half ends, Swansea City 0, Arsenal 3.
Substitution, Arsenal. Alex Iwobi replaces Mesut Özil.
Corner, Arsenal. Conceded by Lukasz Fabianski.
Attempt saved. Mesut Özil (Arsenal) left footed shot from the right side of the box is saved in the bottom right corner. Assisted by Calum Chambers.
Attempt blocked. Modou Barrow (Swansea City) left footed shot from outside the box is blocked. Assisted by Jonjo Shelvey.
Attempt blocked. Alexis Sánchez (Arsenal) right footed shot from the right side of the box is blocked. Assisted by Mesut Özil.
Ashley Williams (Swansea City) is shown the yellow card for a bad foul.
Foul by Ashley Williams (Swansea City).
Alexis Sánchez (Arsenal) wins a free kick on the right wing.
Substitution, Swansea City. Eder replaces Bafétimbi Gomis.
Substitution, Swansea City. Leon Britton replaces Ki Sung-yueng.
Substitution, Arsenal. Kieran Gibbs replaces Joel Campbell.
Substitution, Arsenal. Calum Chambers replaces Olivier Giroud.
Delay over. They are ready to continue.
Delay in match Ashley Williams (Swansea City) because of an injury.
Attempt missed. Joel Campbell (Arsenal) left footed shot from outside the box is close, but misses the top left corner. Assisted by Alexis Sánchez following a fast break.
Substitution, Swansea City. Modou Barrow replaces Jefferson Montero.
Corner, Swansea City. Conceded by Petr Cech.
Attempt saved. Ashley Williams (Swansea City) left footed shot from outside the box is saved in the bottom left corner. Assisted by Kyle Naughton.