Liverpool strife shows Arsenal it's a long way back after UCL exile
It is the closest they will probably ever come to experiencing the anxiety and fear of a relegation battle, but make no mistake, Arsenal will be peering over a cliff this Sunday with a view every bit as chilling as that which faces Sunderland, Middlesbrough and Hull City as they stare into the abyss of the Championship.
As for Liverpool, currently sitting a point clear of Arsenal in fourth place ahead of this weekend's final round of Premier League fixtures, the nervous tension will also be affecting every one of Jurgen Klopp's players and the club's supporters because they are on the brink of reclaiming something which, not so long ago, had appeared to be an annual formality.
Champions League qualification, or the failure to make it, has become the equivalent of winning and losing a battle to stay in the Premier League for English football's most powerful clubs.
Arsenal have so far been immune to the devastating effects that can be triggered by missing out, having qualified for the Champions League in every season this century, but they are now approaching their day of reckoning.
And Liverpool's fate since tumbling out of the Champions League picture in 2009-10 serves as a warning to Arsenal, and Manchester City -- who are also still in need of a point to confirm a top-four finish -- of the black hole that awaits if they tumble into the Europa League by failing to secure a top four position this weekend.
So here is the state of the play in the race for the top four ahead of Sunday's season finale.
City will be certain of the top four if they earn a point at Watford on Sunday. Even if Pep Guardiola's team were to lose at Vicarage Road, Arsenal would need a five-goal swing in their favour to overhaul City and that would require a demolition of Everton at the Emirates.
The real fight is between Arsenal and Liverpool. If Liverpool fail to defeat relegated Middlesbrough at Anfield, an Arsenal victory will see Arsene Wenger's team climb into the top four at Liverpool's expense.
But if Liverpool win, Arsenal will be consigned to fifth and that is when the problems will begin.
And it will not just mean a battle to keep hold of Alexis Sanchez. Far from it.
In the early years of the last decade, Newcastle United and Leeds United performed well in the Champions League before failing to qualify again via the Premier League and both clubs have paid a heavy price for over-stretching simply to remain among Europe's elite.
The Leeds meltdown has been well-documented and, having gone from Champions League semifinalists in 2001 to relegated from the Premier League three years later the Elland Road club continue to fight in vain to return to the top flight.
Newcastle's decline has been more of a slow-burner, but they have been relegated, and promoted, twice, since last competing in the Champions League in 2003.
Arsenal are too strong and financially robust to suffer a Leeds or Newcastle-style downturn. The accumulated wealth of two decades in the Champions League will cushion their fall into the Europa League.
In football terms, they are too big to fail for a prolonged period, but with at least six clubs now challenging for four Champions League places in England, they cannot expect a smooth route back if they miss out this time.
Liverpool have discovered this harsh reality since Rafa Benitez's team crashed out in the group stage in 2009-10.
Champions League winners in 2005, runners-up in 2007, semifinalists in 2008, Liverpool had regained their status as European royalty during the first decade of this century, but it counted for nothing once they dropped out in 2010.
Tottenham Hotspur overhauled them initially, but then along came City, funded by Abu Dhabi's petrodollars, and Liverpool found that the combination of a loss of Champions League earnings, the emergence of wealthier rivals and competing in the Europa League proved too difficult to overcome.
They returned to the Champions League in 2014-15 as Premier League runners-up the previous season, but failed to progress beyond the group stage.
Liverpool's qualification by finishing runners-up in 2013-14 was a key indicator as to the value of missing out of the Europa League, however.
With no European football to focus on, Brendan Rodgers' team were fresh and focused, almost winning the title for the first time since 1990.
The only two English clubs who have missed out on the Champions League and regained their place after a one-year absence are Manchester United and Chelsea, in 2014-15 and this season, respectively.
On both occasions, United and Chelsea had failed to qualify for Europe the previous season, so their lack of Europa League football helped them secure a return to the Champions League.
Arsenal will not have that advantage next season and, as United have discovered during this campaign, a 15-game slog to the final takes a heavy toll on form and fitness, with league results suffering as a consequence.
Liverpool finished eighth last season after progressing to the Europa League final, before losing to Sevilla, and United will end this season in sixth.
It is as though missing out on the Champions League brings a double punishment -- of reduced finances/prestige and an arduous route back via the Europa League.
No team has won the Premier League title after starting the season in the Europa League and that is another issue which Arsenal and Wenger may have to address.
So the stakes are high this weekend because it is not just about missing out on the Champions League this season.
Once you are out of it, even if you are as powerful as United and Liverpool, it is increasingly difficult to get back in and Arsenal may finally be about to discover that for themselves.
Mark Ogden is a senior football writer for ESPN FC. Follow him @MarkOgden_