GiveMeSport live from Emirates Stadium
Arsenal were handed a cruel taste of their own medicine by Champions League rivals Anderlecht at the Emirates this evening, somehow failing to earn maximum points despite being three goals to the good with just 58 minutes on the clock.
Alex Oxlade-Chamberlain's crisp finish early in the second half followed up goals from Mikel Arteta and Alexis Sanchez to have the Gunners within touching distance of a confirmed place in the last 16 for a 12th successive season, but plucky Anderlecht had other ideas.
Quite incredibly Arsenal collapsed after former Portsmouth right-back Anthony Vanden Borre of all people scored from both open play and the penalty spot, setting up a nervy finale which saw substitute Aleksandar Mitrovic beat Per Mertesacker to head home a dramatic late slice of sweet revenge for the visitors.
For Arsene Wenger's side it was a particularly bitter pill to swallow, with all the momentum of Lukas Podolski's late winner against tonight's opponents in Belgian a fortnight ago, and comfortable wins over Sunderland and Burnley, taken away in one fell swoop.
It was also an alarmingly frail climax to a match in which Arsenal were hardly playing what you would describe as top-class opposition, which was shown by wild celebrations from the visitors with their fanatical away support more than five minutes after the full-time whistle.
Heads will need to roll in the Arsenal dressing room after a late collapse on this scale, but who should be the target of Wenger's axe in particular? Let's look at the player ratings and find out.
Calum Chambers: 5
Bright start full of early attacking endeavour was undone by a shabby-second half-display where his one weakness as a full-back at the highest level was exposed, namely pace. At fault for the first goal Arsenal conceded and simply had to do better by showing his man down the line, even if Vanden Borre was offside in the centre
Per Mertesacker: 5
Flirted with danger on a few occasions and was very nearly exposed by raw pace on the counter by Anderlecht, but used his experience to emerge unscathed. Needs to do more from set pieces in an attacking sense, with Arsenal unable to make the most of a ridiculous corner count they accumulate nearly every week. Failure to win that crucial late header against Mitrovic ultimately proved costly.
Nacho Monreal: 5
Spanish utility man looked to be cruising towards another night of welcome obscurity at the heart of central defence, until a needless shove in the back presented Anderlecht with a penalty and a lifeline they scarcely deserved. On this evidence pressure from a higher calibre of opposition will produce mistakes.
Kieran Gibbs: 7
Very comfortable night's work for Gibbs, which will relieve Arsenal fans on his second appearance in four days. Will need more protection in bigger matches though it has to be said.
Mikel Arteta: 7
Mixed bag of a night for the Arsenal skipper, who broke the deadlock with a calm spot kick but saw his passing largely fall well below the required standard. Was withdrawn as a precaution on the hour mark and just can't seem to catch a break on the injury front this season, which must be a huge concern to his manager.
Aaron Ramsey: 6
Welshman was back in the starting XI after a two-game absence and couldn't quite find his rhythm, despite working hard and making plenty of intelligent runs out towards the right-hand side. Patience required from Arsenal for the midfield maestro to find top form once again.
Santi Cazorla: 6
Clearly enjoying the freedom his current advanced role in the starting XI affords, although from a tactical viewpoint I'm not sure Arsenal can justify it. Link-up play with Sanchez was a delight at times, but becomes a passenger if teams break quickly in the same way Anderlecht regularly did.
Alex Oxlade-Chamberlain: 8 (Man of the match)
Heavily involved throughout after a bright start, using his raw pace to burst down the right flank. A switch in wings worked to his benefit and saw him tear apart Anthony Vanen Borre to score the third, producing a clinical finish into the corner to match a brilliant move through the gears in the penalty area. Arsenal need that on a more regular basis.
Alexis Sanchez: 8
Arsenal's £35m superstar continued his rich vein of form with his fifth in three matches and 11th of the season in all competitions, an instinctive beauty of a finish into the bottom corner after Santi Cazorla's free kick had come back off the wall.
Also helped create the opener with a clever through ball down the channel for Danny Welbeck to chase, though the link play between the two still needs work. With the right supporting cast could be absolutely unstoppable.
Danny Welbeck: 6
Didn't get the goal his endeavour merited, but that wasn't for a lack of trying. Used raw strength to win a penalty kick after 25 minutes and regularly made the right run across the defender towards the near post in search of crosses,
Mathieu Flamini: 5
Failed to impose himself on the match after replacing Arteta, which is saying something because Arsenal were in desperate need of midfield clout as a nerve-jangling finale wore on.
Tomas Rosicky & Lukas Podolski: 5
Both came on with very little time to make an impact.