When news broke of Unai Emery’s Arsenal departure on Friday morning, the decision was met with relief and sparked hope that the club’s fortunes may turn around. But, the hierarchy at the Emirates now have a crucial call to make on the Spaniard’s successor. Get it wrong, and the Gunners could be in for a repeat of the past 18 months.

The problems surrounding Emery and his Arsenal side appeared to spring up just a few weeks ago, and although the problems can also be traced back to the end of last season, the issues stem from May 23, 2018, the day of his appointment.

Why? It's simple. He was the wrong choice.

When the original shortlist to replace Arsene Wenger was drawn up, Emery's name was not on it.

It looked as if the job was Mikel Arteta's - with the Arsenal big admires of their former midfielder turned Manchester City coach - but Emery's late entry into the frame and subsequent presentation to the club's hierarchy saw him secure the role.

It was the wrong call.

Despite winning a league title with Paris Saint Germain, his shaky spell in the French capital told Arsenal everything they needed to know. An inability to control a star-studded squad, instructions clearly not getting through due to the language barrier and that 6-1 defeat in Barcelona provided all the warning signs. They were ignored.

The decision to pick Emery over Arteta came down to this, a lack of bravery in appointing an untested manager and picking a perceived 'safe pair of hands' rather than taking a risk.

Arsenal now must learn from that mistake. If they fail to do so, the past 18 months could happen all over again.

Wolves boss Nuno Espirito Santo is among the front-runners to take over at the Emirates, but much like Emery his appointment would be somewhat uninspiring and a relatively safe option.

Former Juventus boss Max Allegri has also been linked - as he was just over 18 months ago - but having managed a team of stars at the Italian giants, he could well struggle with Arsenal's dysfunctional squad.

The Gunners must instead look at the downfall of once-great rivals Manchester United, and learn from their errors.

In David Moyes, Louis van Gaal and Jose Mourinho, the Red Devils appointed a string of managers who were all perceived as a 'safe pair of hands' - much like Emery was - in the wake of Sir Alex Ferguson's departure.

Those decisions have seen them fall from a dominant force that every team feared to merely another member of the top six that are no longer major players.

Yes, it's true that happened to Arsenal a long time ago, but now is the time to make an appointment that will reinvigorate and rejuvenate.

The way to do this is to target a young, hungry manager who knows the club, understands the values and the importance of the badge. Luckily for Arsenal, there are plenty of those around.

Freddie Ljungberg - who has been placed in caretaker charge following Emery's sacking - fits the bill perfectly, as does Arteta, although the club may have burned their bridges following his 2018 snub.

Further afield, Invincibles skipper Patrick Vieira is now in charge at Nice and making a name for himself, while Giovanni van Bronckhorst is another option.

Appointing a young and relatively inexperienced manager is certainly a risk but it has its benefits, with a determination to make a name for themselves chief among them.

The knowledge of the club is also important, with Frank Lampard at Chelsea - although very early into his tenure - a good example. With the situation at Arsenal, it becomes even more important.

Arsene Wenger built a dynasty in north London, much like Sir Alex did in Manchester, and leaving that shadow can be a daunting task.

A young manager, hungry to make a name for themselves and step out of that shadow, but with an understanding of the traditions at such historic clubs would be best placed to do just that.

It's not without risk and there may be teething problems, but Arsenal have to be brave and bold in the coming weeks as they search for Emery's successor. The same mistakes that were made 18 months ago cannot be made again this time around, or the club risk getting stuck on the endless merry-go-round of mediocrity.