Valencia have been waiting 12 years for this moment.
Tomorrow night's Champions League Group H game, likely decisive in determining who advances to the round of 16, is being billed as Los Che's biggest in the competition since they were felled by Chelsea in the 2006-07 quarter-final.
On that occasion Michael Essien completed a comeback in added time of the second leg to send Chelsea through 3-2 on aggregate and crush Valencia’s spirit. Seeing as they have not returned to the final eight since it is a defeat that still rankles.
Tomorrow is inevitably being framed as a chance to exact some revenge, especially when a loser would almost certainly end up in the Europa League, but it is also part of a wider opportunity for Valencia to show that they deserve to be considered among Europe's elite again.
And yet there remains a feeling of unease at a club that has a startling knack for eating itself.
The reverse fixture at Stamford Bridge on September 17 will be mostly remembered by Blues fans for Ross Barkley demanding to take that late penalty and subsequently missing.
A few days earlier the popular head coach Marcelino, who guided the club to their first trophy in 11 years last season and achieved Champions League qualification, had been sacked following a falling out with owner Peter Lim.
The genesis of that row had stemmed from the club being unable to sign any of the players Marcelino wanted but it was rooted in a clash of egos and, as is invariably the case in such situations, the owner wielded the axe.
Supporters were up in arms, the players boycotted their media duties in London and Albert Celades, whose previous experience had extended to being assistant manager for Julen Lopetegui's Spain and Real Madrid, was swiftly appointed as Marcelino’s replacement.
While the players were giving the silent treatment in West London, Celades had to fend off questions that ranged from his impressions of the row between Marcelino and the hierarchy to whether he would be cut out for the job.
Since then they have found a semblance of normality off the pitch (well, at least the coach is still in place and the players are talking again) but results remain consistently inconsistent.
Having won three games in a row before the international break, their best run of the campaign, on Saturday they led away to Real Bets but lost 2-1, conceding a Sergio Canales free kick in the 93rd minute with goalkeeper Jasper Cillessen coming in for some criticism for his failure to keep it out.
Valencia, now 10th in the league table, attacked fluidly early on but lost focus in the second period and Celades rejected the idea that they were distracted by Chelsea.
But no one is underplaying the importance of tomorrow's game. Presuming that Ajax add three points away to Lille, the winner at Mestalla will likely join the Dutch champions in the knockout stages.
Chelsea have not played so stagnantly since September's meeting and their performances have been more impressive away from home.
Along with questions over Cillessen’s form, Valencia are also dealing with some notable absentees – especially in midfield where Francis Coquelin, Geoffrey Kondogbia and Denis Cheryshev are all ruled out. Daniel Wass, usually a wing back, is likely to start in the middle.
“We are up for this and we have a great chance [to progress],” Celades said. “We will need to be at our best if we are going to win.”
Their motivation will be high but Los Che are under even more pressure than Frank Lampard’s young team. Dani Parejo, the 30-year-old captain, said it is a game that “must be treated like a final” but the result may well be decided by which team can handle the heat.
