Unai Emery's first season in charge at Arsenal is in danger of imploding unless the Spaniard can again prove himself to be a Europa League specialist and cover up an alarming dip in the Gunners' Premier League form.
Arsenal have lost four of their past five league games to Everton, Crystal Palace, Wolverhampton Wanderers and Leicester City to slip down to fifth and relying on more favours from Chelsea or Tottenham to have any chance of a top-four finish.
However, winning the Europa League would also offer a much-needed return to the Champions League next season after a two-year absence.
Emery is a specialist in Europe's second-tier competition, winning it three times when at Sevilla, and he is also well acquainted with Arsenal's semi-final opponents, Valencia, who he managed between 2008 and 2012.
Emery also did a stellar job at the Mestalla, leading Valencia to three consecutive third-placed finishes behind dominant Barcelona and Real Madrid sides managed by Pep Guardiola and Jose Mourinho.
However, doubts remain over his ability to lead Arsenal's rebuild back to the heights they once enjoyed under Wenger.
The same defensive issues that haunted the Frenchman's final years in charge have been in evidence in recent weeks, conceding three times in three consecutive league defeats for the first time since 1967.
Emery has constantly changed personnel and formations, but is yet to find the right balance with one of his two star forwards Alexandre Lacazette and Pierre-Emerick Aubameyang often left out.
Yet, there have been notable successes. Top-four rivals Tottenham, Chelsea and Manchester United were all beaten at the Emirates this season and Emery's men won home and away to Napoli in the Europa League quarter-finals.
Valencia find themselves in a similar situation to Arsenal in looking at the Europa League to save a disappointing domestic season.
A shock 1-0 home defeat to Eibar on Saturday leaves Los Che sixth in La Liga and three points outside the top four with three games left.
Former Arsenal defender Gabriel Paulista will return to the Emirates on Thursday and wants to mark Valencia's centenary year in style.