Unai Emery's side were heading for a demoralising defeat, three days after losing meekly to Sheffield United in the Premier League, but substitute Pepe's late intervention kept the Gunners top of Group F with a maximum nine points.
Arsenal's young guns continued to shine as they dismantled Standard Liege 4-0 on a hectic night of Europa League action that produced a full house of Spanish victories on Thursday. A summary of the matches.
Barcelona will travel to Borussia Moenchengladbach for their Champions League match on Wednesday without Lionel Messi but the Spaniards have enough options and firepower to plug the gap left by the Argentine, coach Luis Enrique said.
Napoli went down 3-1 at home to RB Leipzig, Arsenal and AC Milan enjoyed comfortable away wins, and Borussia Dortmund's Michy Batshuayi scored twice to secure a 3-2 victory in Europa League last 32, first leg action
Three time European champions Inter Milan were stunned 2-0 at home by Israeli side Hapoel Beer-Sheva and Manchester United were floored by a late goal from Feyenoord as the Europa League group stage got underway on Thursday.
Holders Sevilla maintained their Europa League challenge with a 1-0 win over Rijeka in a winner-takes-all clash on Thursday.
Jose Callejon took advantage of Napoli's numerical advantage in the 48th minute of the playoff round second leg tie, handing them an away goal which, added to their 2-0 win from the first leg, effectively ended Nice's challenge as it left the French side needing to score four goals.
The value of an in-form striker was underlined as Tottenham Hotspur, Liverpool and Athletic Bilbao needed goals from pivotal front men to grab vital wins that booked places in the Europa League last 32 on Thursday.
News of all that's transpired on and off the football field.
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Borussia Dortmund snatched a late goal at Atalanta to progress with a 1-1 draw, while AC Milan and Atletico Madrid, both with three-goal leads from the away legs, completed the formality of qualifying with 1-0 wins at home on Thursday.
Chelsea reached the Champions League knock-out stage on Tuesday despite a 1-0 defeat by Basel in Group E after a late Mohamed Salah goal shocked the 2012 title winners, with Jose Mourinho saying they deserved to lose. Barcelona, without Lionel Messi but already into the last 16, went two goals down in Amsterdam but looked a different side in the second half after Ajax's Joel Veltman was sent off.
Zoo director Vladimir Gerasimov believes Cleopatra might have a little better understanding of soccer than other animals.
Rattled by embarrassing domestic defeats, Chelsea looked jittery before Olivier Giroud settled their nerves with a close range tap-in shortly after halftime at StamfordBridge following good work by N'Golo Kante and Willian in the build-up.
Belgium have retained injured Vincent Kompany in their final World Cup squad but put fellow defender Laurent Ciman on standby in case the Manchester City skipper is not fit for their opening match in Russia.
Kazakhstan's Astana fought back to beat a youthful Manchester United side 2-1 at home, Arsenal's woes continued as Frankfurt's Daichi Kamada scored twice to secure a 2-1 win.
IMAGES from the UEFA Champions League last 16 first leg matches played across Europe on Tuesday
News of all that's transpired on and off the football field.
News of all that's transpired on and off the football field
A summary of all the Champions League matches played across Europe on Tuesday
News of all that's transpired on and off the football field
Stephan El Shaarawy took a small step towards refuelling his career at Monaco when the AC Milan loanee came off the bench to rescue a late 1-1 draw against Tottenham Hotspur in the Europa League's second round of group matches on Thursday.
Lionel Messi marked his first start after injury with a goal in Barcelona's 1-1 draw at AC Milan in the Champions League on Tuesday while Fernando Torres got two as Chelsea thumped Schalke and Atletico Madrid's charge continued.
News of all that's transpired on and off the football field
Barcelona and Atletico Madrid led a Spanish Armada into the Champions League last 16 with home wins on Wednesday and in-form Aaron Ramsey steadied Arsenal's boat with a battling win against rocky Borussia Dortmund.
A summary of Wednesday's matches in the UEFA Champions League.
Coach Pep Guardiola was left thrilled after ManchesterCity revived their Champions League bid by beating his old club Barcelona 3-1 in a gloriously open Group C encounter at the Etihad Stadium on Tuesday.
Manchester City's Sergio Aguero scored a hat-trick as coach Pep Guardiola maintained his 100 per cent record at the club with a commanding 4-0 victory against Borussia Moenchengladbach in their rearranged Champions League Group C opener on Wednesday.