It’s not something to be said lightly. After all, no current Premier League manager has served for so long or given so much to the game. Yet this summer Arsene Wenger should leave Arsenal.

Arsenal have not won a trophy since the 2005 FA Cup. That same competition represents the club’s only chance of silverware this season. A win after extra time and penalties this evening leaves Arsenal facing either Sheffield United or Hull City in May’s final. However should Arsenal end the agonising wait for an accolade, it must be Wenger’s swansong, not the beginning of a new chapter for him at the club.

The Frenchman may have the final say on whether or not he signs a new contract, and indeed there has been talk of him being handed £100m to spend in the summer transfer window, but the time is right for Arsenal’s longest serving manager to go.

Incredible to say about a club who have consistently qualified for the Champions League, but Arsenal are stagnant. Their seasons have predictable peaks and troughs. This campaign, while they and their fans remained defiantly certain that their excellent pre-Christmas form would carry through to the end, everyone else waited for the implosion.

It wasn’t Schadenfreude on the behalf of  non-Arsenal supporters and analysts, it was just recognition of the Arsenal condition. Consistently inconsistent. The past few seasons have followed the same narrative. A slow start, concern over Champions League qualification only appeased by a strong finish from February to May.

This season however, boosted by the capture of Mezut Ozil and the form of Aaron Ramsey, Arsenal started strongly. They looked like genuine title contenders in the first few months of the campaign, but it just couldn’t last. The usual problems arose. A lack of strikers, poor performances against the other top teams, a lack of leadership when games got tight.

Heavy defeats to others in the title race have derailed Arsenal’s season and left them fighting for a place in the Champions League once more. Whilst shipping five and six goals against Liverpool and Chelsea respectively, what was more alarming for Arsenal fans was their capitulation to Everton last Sunday.

Watching the game at Goodison Park, there were two major talking points. It was striking to see how much Roberto Martinez’ side looked like the Arsenal of old. A team that passes the ball with aplomb and tears opponents apart with the speed of their play. The second thing was just how indecisive Arsene Wenger was when it came to substitutions.

He’s not a manager to make hurried changes, but with Arsenal 2-0 down at half time to the team threatening to put a stop to their incredible Champions League qualification record,  something had to be done. Leighton Baines and Seamus Coleman were causing all sorts of problems down the flanks. Santi Cazorla was playing too central, allowing Baines space a player of his class can exploit. On the other side, Romelu Lukaku wasn’t being picked up by either Lukas Podolski or Nacho Monreal. This led directly to Everton’s second goal.

With Aaron Ramsay back in the squad after injury and Alex Oxlade-Chamberlain also available, the break or just after was the time to bring these players on and give the Everton midfield and defence something to think about. When did Wenger make these changes? With an hour gone and Everton 3-0 up.

Wenger can’t shoulder all the blame for not making changes in time. The players he selected to start the game have to step up and perform. That just didn’t happen and as a result Arsenal were blown away, not for the first time this season. Leaders seem few and far between on the pitch. Tomas Vermaelen is the captain but with a fully fit squad the Belgian would not make the starting XI. Why is a certified starter not handed the arm-band, someone such as Per Mertesacker or even Jack Wilshere? Because there is no one on the team right now who has shown the necessary leadership to be captain.

Wilshere and Ramsay are definitely future captain material, but they are still young and raw and they need a Patrick Vieira like figure to bring their game on to the next level. Paul Scholes may have drawn the wrath of Arsenal fans for his assessment of Wilshere on Sky Sports a few weeks back but he doesn’t seem the type to court publicity for his opinions. He was just giving his honest opinion.  A Jack Wilshere playing to his full potential would not just be good for Arsenal but for England too.

That is where Arsene Wenger has failed most blatantly, and perhaps the main reason the Gunners have not won a trophy in a decade. Wenger has not brought in a leader to replace the likes of Viera, Martin Keown and Tony Adams. Cesc Fabregas may have become that player had he stayed. Wenger has placed an emphasis on talented youngsters and while that project was and remains admirable it is nothing without the grit that a good leader adds to a side.

Ironically, the one player that could have contributed that leadership, albeit on a temporary basis, was Kim Kjallstrom. The Swede came to Arsenal in January, incredibly while nursing an injury that has kept him out until now. His experience may have been exactly what Arsenal needed for the second half of the season, but the decision to take him on injured, even with his parent club paying the wages while he remained out, was ludicrous.

Arsene Wenger’s detractors will point to Gervinho, Andre Santos, Sebastian Squillaci and others as examples of his inadequacy in the transfer market. That doesn’t do the man justice, as he was also responsible for signing Thierry Henry, bought for £11m and one of the bargains of the Premier League era. Nevertheless, the fact that flop Andrei Arshavin was Arsenal’s record transfer signing until Mezut Ozil shows a stubbornness on Wenger’s part to move with the times financially. While he has bought in some excellent players at reasonable fees, with Santi Cazorla and Oxlade-Chamberlain two recent examples, he has yet to adequately replace Cesc Fabregas in the centre of midfield. Bringing in the 30 year old Mikel Arteta in the same transfer window that as Cesc left, with all respect to the former Everton man, was insufficient compensation for the loss of the younger Spaniard.

Manchester United have been criticised this season for their poor performances, and much of the blame has been put on the board and David Moyes for failing in the transfer market last summer. The last minute purchase of Marouane Fellaini at an inflated price has been questioned and rightly so. The Belgian has yet to prove his worth, and that money may have been better spent on a ball-playing central midfielder. But what of Mezut Ozil’s transfer to Arsenal? £42m for the German who, while undoubtedly a spectacular creative force, occupies a role in the team that other players already at the club could have filled.

The acquisition of Ozil brought Arsenal’s spending over the past three years close to £150m. This has been offset of course by the sales of key players Robin Van Persie, Cesc Fabregas and Samir Nasri for a combined total of around £80m. The loss of this caliber of players certainly impacted on Arsenal’s ability to challenge for trophies, but it must be remembered that Tottenham Hotspur spent over £100m last summer and now look set to change managers for the second time since. Spending lots of money, whether you are a top six club or QPR, leads to expectations from the board and from the fans. Failure to meet those expectations usually proves to be the end for a manager.

David Dein leaving Arsenal in 2007 no doubt hindered Arsene Wenger. As Arsenal’s vice-chairman, he had a big part to play in transfer dealings during first decade of Wenger’s reign. Patrick Vieira, Emmanuel Petit, Thierry Henry, Robert Pires, Robin Van Persie, Cesc Fabregas… All of these players were bought on Dein’s watch. In the interim, the club has been less of a force in the transfer market.

Thierry Henry was the first big-name player to leave in the aftermath of Dein’s departure. In the seven years since, Samir Nasri, Alex Song, Cesc Fabregas, and Gael Clichy to name but a few have followed suit. Wenger said in the summer of 2011 that if Arsenal sold both Fabregas and Nasri the club could no longer be called ambitious. Both players left in August. Former Arsenal player Niall Quinn said recently that if Wenger was to stay at Arsenal past the end of this season Dein should be reappointed. Given that Dein left due to irreconcilable differences with the rest of the board, his return to Arsenal is unlikely.

Dein’s exit left Wenger without a key ally, and it has shown in transfer dealings in the meantime. With the exception of Ozil, there has been no major financial investment in a player in recent years. What Arsenal fan can honestly say that Arsenal have bought a world class striker since Robin Van Persie came to the club in 2004? Eduardo had the potential before his leg-break, but Chamakh? Gervinho? Even Giroud can’t be considered in the same bracket. Wenger’s supporters may point to constraints put on the manager while Arsenal continue to pay off the Emirates Stadium, but if £42m can be spent on Ozil, then why could Arsenal not secure the quality striker they desperately need? Wenger’s reluctance to buy a proven goal-scorer in January has cost them dear this season, with Nicklas Bendtner the only senior replacement for Giroud.

Wenger cannot bring the club any further. Three losses on the trot and the “Wenger Out” brigade are in full voice. Three wins and they are title challengers, before another loss has Wenger vilified by certain sections again. There is no consistency on the field, and no consistency to some of the support off of it. The average level-headed Arsenal fan, who appreciates how much Wenger has done for the club, must also recognize that the time is approaching for the Frenchman to leave. The average Arsena fan is grateful for the Arsenal legends Wenger brought to the club, for the Invincibles, for the style of play that at times made Arsenal better to watch than Barcelona. But the average Arsenal fan, without setting up Facebook pages on the issue, surely knows that it’s time for a new manager to come in and breathe new life into the team.

Wenger’s battles with Alex Ferguson and later Jose Mourinho were some of the most fascinating in Premier League history.  The trophyless Arsenal narrative would be but a bed-time fairytale for young Spurs fans were it not for goalkeeping errors in the 2006 Champions League final and the 2011 Carling Cup final. Arsene Wenger introduced a style of play to the Premier League that entranced Arsenal fans and neutrals alike, but this summer he must leave before his legacy is tarnished.

Sheffield United and Hull will have other ideas but an FA Cup to end almost a decade of drought would be the perfect goodbye gift from Arsene to Arsenal.