Borussia Dortmund ended Arsenal's unbeaten start to the UEFA Champions League with a 2-1 win at the Emirates Stadium on Tuesday.
Arsene Wenger, who celebrated his 64th birthday on Tuesday, saw his Arsenal side start slowly and the Premier League leaders were quickly punished when Henrikh Mkhitaryan shot past Wojciech Szczesny.
Olivier Giroud was on hand to draw Arsenal level shortly before the break, as he took his tally for the season to nine, before Robert Lewandowski grabbed the winner for last season's beaten finalists eight minutes from time.
The hosts brought former Dortmund midfielder Tomas Rosicky in for the injured Mathieu Flamini, while Ramsey regained his starting spot ahead of Santi Cazorla, having come off the bench to score his fifth Premier League goal of the season against Norwich City on Saturday.
Jurgen Klopp served the second and final game of his touchline ban after being sent to the stands against Napoli in September and he made three changes from Saturday's 1-0 win against Hannover.
Mats Hummels returned in defence along with Marcel Schmelzer, who made his first start for the club since September following a thigh injury.
Jakub Blaszczykowski was preferred ahead of Pierre-Emerick Aubameyang.
Assistant coach Zeljko Buvac took Klopp's place in the dugout and saw Dortmund enjoy more possession early on, but were unable to test Szczesny, with Kevin Grosskreutz and Hummels both firing well over in the opening six minutes.
Marco Reus powered an effort just past Szczesny's right-hand post before the Germany international dispossessed Ramsay well to allow Mkhitaryan a sight on goal after 16 minutes.
Robert Lewandowski then played the loose ball into the Armenia international, who fired low past a helpless Szczesny to put the visitors in front with his first Champions League goal for the club.
Arsenal's first attempt came six minutes later, with Laurent Koscielny heading a Mesut Ozil free-kick over Roman Weidenfeller's bar before Jack Wilshere almost got on the end of a clipped Rosicky throughball, only for it to get away from him and roll behind for a goal kick.
The home side continued to grow into the game and were almost rewarded when Rosicky's shot was blocked on the line by Neven Subotic, with Weidenfeller beaten, eight minutes from the break.
The Premier League leaders were level just three minutes late, however, courtesy of Giroud's close-range finish after a defensive mix-up from the visitors.
Bacary Sagna's delivery clipped Subotic, causing Weidenfeller to fumble, with Giroud on hand to level in emphatic fashion as he scored his second in as many Champions League matches.
Grosskreutz had the first chance of the second half for the visitors, but he saw his sidefooted effort saved easily by Szczesny before substitute Cazorla hit the angle of post and bar with a curled effort from outside the area.
Dortmund got the crucial goal after 82 minutes, courtesy of Lewandowski's 10th goal of the season.
The Poland international ghosted in at the far post to calmly stroke home Grosskreutz's delivery and ensure Dortmund ended Arsenal's 12-game unbeaten run in all competitions.
|Coach: A. Wenger|
for J. Wilshere 58'
for A. Ramsey 86'
for T. Rosický 89'
|Andre Gomes: Barcelona suit my identity better than Real Madrid|
|Niersbach to appeal FIFA ban|
|Barcelona agree Mascherano renewal|
|Fernandinho can play in 10 positions - Guardiola|
|Reading´s kit launch is out of this world|
|Ben Arfa: I do not want to be PSG´s star player|
|FA Cup to trial fourth substitute|
|We want Balotelli and he wants us, says Besiktas chief|
|Crowd welcomes Higuain as he arrives for Juventus medical|
|Guardiola warns Man City stars: If you´re not fit, danger is coming|
|Mkhitaryan prepares to prove himself at United|
|Cavani: No pressure replacing Ibrahimovic|
|Wenger vows to keep transfer plans ´secret´ after Lacazette snub|
|Brannagan open to Championship loan move|
|Wenger wants to sign Mertesacker replacement|
|Ancelotti: Bayern´s transfer business done|
|Brisbane Roar sign former Danish international Kristensen|
|Verratti, Luiz missing for PSG|
|Sounders part ways with foundation coach Schmid|
|Mane turned down Manchester United for Liverpool|
|Zidane on Pogba: Until August 31, anything can happen|
|Mkhitaryan driven by father´s death|
|Inter rejected Napoli offer for Icardi, says president|
|Clichy: City fighting fit after Guardiola pizza ban|
|Everton and Burnley win as Hull are held|
|Ajax held by PAOK after Cillessen howler|
|Conte left frustrated by ´crazy´ money in transfer market|
|Neymar makes Barcelona case to Gabriel Jesus|
|Rostov comeback twice for Champions League draw with Anderlecht.|
|Arsenal defender Mertesacker set for lengthy lay-off|
|Conte not selling ´fantastic´ Matic|
|Ibrahimovic keen on MLS and Beckham´s Miami project|
|Neymar: I play for Messi, he´s the man|
|Barcelona reveal details of Andre Gomes deal|
|Suarez bullish over Barcelona prospects|
|Ajax claim Napoli keen on Milik to replace Higuain|
|Totti labels Higuain´s Juventus move ´a disaster´|
|Juventus confirm Higuain deal|
|Pato to Villarreal ´in the final stage´|
|PSG sign Lo Celso|
|Muller: Beating Dortmund will be more fun this season|
|Juventus sign Higuain from Napoli for €90m|
|Pastore: I´m like God in Paris|
|Injured Lanzini out of Olympics|
|Allegri unperturbed by Higuain fee|
|Menezes replaces Bento at Cruzeiro|
|Sporting rejected major bids from Inter and Liverpool for Joao Mario, claims father|
|Pochettino pleased by Tottenham despite Juventus defeat|
|Eriksson: Allardyce the right man for England|
|Mourinho makes United train after stepping off plane from China|
|Hazard can still match Messi, says Pedro|
|Pjanic shows there is life at Juve, with or without Pogba|
|Juventus 2 Tottenham 1: Benatia bags win for Serie A champions|
|Dembele: I am not the Bundesliga´s next superstar|
|Lyon claim €35m Arsenal offer for Lacazette rejected|
|Donnarumma dreaming of Milan captaincy as he eyes long-term stay|
|Robson: Ibrahimovic can match Van Persie´s first year at United|
|Rooney should remain England captain - Eriksson|
|Emery wants new striker at PSG|
|Santos accept Juventus bid for Gabriel|
|Eriksson expects Sweden to try and tempt Ibrahimovic out of retirement|
|Spurs signing Janssen almost quit|
|Leicester stay best for Mahrez - Ranieri|
|Allardyce to take Mourinho cue on Rooney|
|Ings ready to outdo big-money signings|
|Henderson optimistic over Liverpool campaign|
|Allardyce hardened to the challenge of England post|
|Barcelona announce record revenues for 2015-16|
|Moyes enjoys Sunderland win as Palace beat Colchester|
|Stoke complete Allen signing|
|Roma coach Spalletti warns suitors off Manolas|
|Cresswell out for up to four months with knee injury|
|Burnley fan banned by club for racist abuse|
|Dad won´t let me play at the Olympics - Larsson Sr pulls rank|
|Kostic joins Hamburg on five-year deal|
|Tevez: I´d turn down Chelsea and Napoli to stay at Boca|
|Mayoral inspired by Benzema for Wolfsburg stint|
|Allardyce straight into competitive action with England|
|Liverpool, Sevilla fined for Europa League final incidents|
|Barcelona seal Guillemenot signing as part of new Servette deal|
|Niersbach handed one-year ban over World Cup corruption|
|Chelsea and Everton ´still interested´ as Koulibaly eyes Napoli exit|
|´Still working hard´ - Balotelli trains with Liverpool kids|
|Winter breaks, long-ball football and the World Cup: Allardyce in his own words|
|Inter warn Napoli Icardi is not for sale|
|Zanetti wants Simeone back at Inter|
|Stoke snap up Sobhi|
|PSG tougher under Emery - Lucas Moura|
|Totti not ready for retirement - Pallotta|
|Confident Allardyce reveals plan for England success|
|Pochettino to discard three Tottenham players|
|Allardyce: Rooney must wait for captaincy decision|
|Aubameyang: I will only leave Dortmund for Real Madrid|
|Allegri silences questions on Pogba|
|Bruce stands by decision to quit Hull City|
|Pochettino: Not the right time for Argentina job|
|Inter yet to approach De Boer with Mancini exit rumoured|
|Ancelotti trusts me more than Guardiola - Ribery|
|Wijnaldum rejected Everton for Klopp|
|Pre-season Manchester derby cancelled|
|Coutinho excited by ´fast´ Liverpool recruits|
|Cristiano Ronaldo and Conor McGregor step into the ring together|
|Mancini coy on reports linking Icardi to Napoli|
|Nolito reveals why he chose Man City over Barcelona|
|Inter 1 Paris Saint-Germain 3: Icardi absence in defeat fuels Napoli talk|