Arsenal 1 Monaco 3: Five things that we learnt, including Danny Welbeck sets tone and Arsene Wenger's team appear to have learnt nothing

The Gunners slumped to a 3-1 loss against their French opponents

Kondogbia comes of age to run the show

If this was a night for players to show how they could cope with responsibility and pressure, few did better than Geoffrey Kondogbia. He is just 22 years old but he had to glue Monaco’s midfield together, in the absence of suspended linchpin, Jérémy Toulalan.

Kondogbia might have wilted but instead delivered a performance of impressive authority, protecting the two stand-in centre-backs, tracking the runs of Alexis Sanchez and Mesut Özil and using his athleticism to cause problems at the other end.

Of course, Kondogbia’s opening goal was fortunate. Had it not hit Per Mertesacker it would likely have been saved. But it was to Kondogbia’s credit that he made the run, showed for the ball, and took the shot. That itself was more audacity and initiative than Arsenal showed for much of the evening.

Giroud sleepwalks into a nightmare up front

The one weakness of Olivier Giroud’s time at Arsenal, the biggest difference between him and the very best, is that he did not score in the big games. This was a chance for him to dispel that notion. Instead he reinforced it emphatically, with a performance that would have been implausible even as a nightmare.

Giroud missed three chances in the first half and three sitters in the second half, and was withdrawn after only an hour. His final minutes on the pitch were difficult to watch: he miskicked from close range at the near post, directed a free-header from a free-kick over the bar and, for the coup de grâce, skied a close-range rebound after Alexis Sanchez’s shot was saved.

Welbeck miss sets tone for Arsenal’s night to forget Even in an 180-minute

European tie, the momentum can shift decisively at the very start. Only 90 seconds had gone when Danny Welbeck span Elderson, ran through on goal, but shot over the bar. In the fifth minute Welbeck was about to score but Aymen Abdennour beat him to it. Had Arsenal got a goal from either of those it would have been a very different evening.

In that sense this was reminiscent of the equivalent fixture from last year. They had started briskly against Bayern Munich, one year and one week ago, but Özil missed a penalty after eight minutes. That was effectively it for Arsenal in that tie, as they lost belief, lost their goalkeeper and eventually lost 2-0. This Monaco side are nowhere near the level of Pep Guardiola’s team, but the deflationary effect of an early miss is the same.

Danny Welbeck in action (GETTY IMAGES)

The old problems resurface ... with a vengeance

While the famous 2-0 win at Manchester City last month has been held up as transformative, in terms of Arsenal’s big-game mentality , the evidence since is starting to suggest otherwise. Not only are City now remarkably permeable at home, but the old Arsenal problems, about taking the game to the top teams, seem to have returned.

At White Hart Lane in the derby with Spurs, Arsenal scored early but were then pinned back. Here, they completely blew it. From 1-0 down this was salvageable but the second-half performance was one of a side unable to cope with the mental demands of the contest: panicking with the ball, open at the back, knocking themselves out of Europe when they had such a good chance.

Arsene Wenger pictured during Arsenal's defeat to Monaco (GETTY IMAGES)

Just what have Wenger’s men learnt in recent years?

An awful lot is made of “European experience” but this is a competition that Arsenal have been playing in for 17 years, in a knockout stage that they almost always reach. While Monaco did lose the Champions League final in 2004, they have not played a knockout game in it for the last 10 years. Yet last night they schooled Arsenal. For all the fears that they would park the yacht, they were always dangerous on the break, waiting for their opportunities, ruthless in attack. It made you wonder what Arsenal had learnt in the last few years, except for how to collapse under the lights, under pressure.