They were not good enough to see the job through – and now the whole season is hanging by a thread.
Arsenal were desperately poor, they were punished with a devastating 94th minute equaliser and Slavia Prague’s precious away goal leaves Mikel Arteta with a mountain to climb.
But the grim truth is that Arsenal got what they deserved because they look a second rate team which is flatlining towards mediocrity.
Arsenal wasted a host of chances, hit the woodwork twice and then eventually went ahead through substitute Nicolas Pepe’s 86th minute opener.
A strong, disciplined and experienced team should be able to see out the game with such little time left, take the narrow victory and count their blessings.
But Arsenal are none of those things and they succumbed to Tomas Holes’ headed injury time leveller in a typical kamikaze goalmouth scramble which again highlighted the home side’s defensive frailties.
This was Arsenal’s last chance to save their season, their last hope of a passport into Europe next season and now they face an exit which will be a huge blow to the club on and off the pitch.
Arsenal have not had a season out of Europe since 1995/96 and yet this team is going backwards fast under Arteta because they look jaded, shattered and desperately short of confidence and belief. They barely showed the sort of passion or intensity needed for such a big game.
Arteta made a big call by leaving Pierre-Emerick Aubameyang out of his starting line-up, the Arsenal captain was only a second half substitute but can have few complaints after his recent dismal displays.
But, sadly for Arteta, it was Alexandre Lacazette who was the worst offender when it came to missed chances as he crashed a shot against the bar with the goal at his mercy.
Far too many other big players did not show up as big summer signing Thomas Partey was anonymous again, Emile Smith-Rowe had a rare off night and there are only so many times that teenager Bukayo Saka can come to the rescue.
Arsenal look a mess, in need of a rebuild and yet if they do not get into Europe then they will be looking at having to sell players to cut their losses rather than buy them.
Suddenly, Arteta looks a manager in trouble, the FA Cup completely changed the mood last season and yet this time they are running out of luck.
Slavia Prague have been on a hell of a run, unbeaten in their domestic season and yet are hardly European heavyweights despite putting out Glasgow Rangers and Leicester this season.
They started well but Arsenal took over and Saka missed a gilt edged chance in the first half after going through as Arteta’s men slowly but surely found some sort of momentum.
It was a slow, lacklustre display but Willian crashed a free kick against the post before Lacazette missed the biggest chance of the night.
Lacazette robbed Oscar Dorley on the halfway line, went clean through, Slavia keeper Ondrej Kolar went down early to give the Frenchman the whole goal to aim at but he still skewed his shot against the bar.
Finally, Arteta sent for the cavalry as Pepe and Aubameyang came on and the two combined after 86 minutes. Aubameyang’s snatched through ball sent Pepe away, the £72m winger raced through and then cleverly dinked the ball over the keeper.
But still Arsenal were not safe. Not with their defence. Over came Lukas Provod’s corner, it created panic and there was Holas who lost his marker Cedric Soares at the back post to head home a goal which might just finish Arsenal’s season.