The Gunners succumbed to their 13th league defeat of the season - courtesy of a Bernd Leno own goal - in a 1-0 loss against The Toffees.
There is no need to stress the importance of Thursday's semi-final first leg fixture, with both clubs' respective seasons pinned on European success.
Return of the Big Guns
Arsenal have struggled with a copious amount of injuries to pivotal first team players in recent weeks. The likes of David Luiz, Kieran Tierney, Martin Ødegaard and Alexandre Lacazette have all spent time on the treatment table, whilst captain Pierre-Emerick Aubameyang contracted malaria whilst on international duty with Gabon.
However it appears as though Bruno Mazziotti - Arsenal's new recruit in the physio department - has worked wonders as Arteta has confirmed all of the above players are in contention to feature on Thursday night.
The return of Tierney is perhaps the most important, as The Gunners have struggled to create ample opportunities without the marauding Scotsman.
The return of Tierney will also allow Xhaka to return to his preferred position at the heart of Arsenal's midfield to partner Thomas Partey, who has somewhat struggled alongside the likes of Dani Ceballos and Mohamed Elneny.
Arteta will no doubt be glad to have his senior strikers back as both Aubameyang and Lacazette have illustrated their pedigree on the European stage before, scoring all seven goals in Arsenal's 7-3 aggregate win over Valencia in the 2018/19 Europa League semi-final.
Despite his shortcomings in England's capital, Emery remains a serial Europa League winner having won the competition three times with Sevilla.
Emery also knows Arsenal well having spent 18 months in charge of The Gunners, meaning he has inside information on a host of players and will know what to expect from his former club.
Despite their turbulent season, Villarreal have been dominant in the Europa League this season, winning 11 out of their 12 games and winning all six of their home ties.
Therefore Arteta and his squad will need to play their own game and avoid any complacency if they are to be in with a chance of reaching their second Europa League final in three years.
Onus on Defensive Solidity
Villarreal have the ability to be devastating on the counter attack, as highlighted by their free-flowing attacking football over the two legs against Dinamo Zagreb in the Europa League quarter-final.
The likes of Moi Gómez and Samuel Chukwueze provide width to Villarreal's attacking play, whilst Gerard Moreno and Paco Alcácer supply the devastating finishing touch.
If Arsenal's fullbacks - most likely Cédric Soares and Tierney - push up high and are not covered, Arsenal could well be on the receiving end of a Villarreal counter-attack.
One area of interest for Arteta will be Villarreal's ageing - and relatively immobile - midfield.
Nevertheless, coming away from the Estadio de la Cerámica with a clean sheet and an away goal will prove instrumental if Arsenal are to overcome a stern Villarreal side and progress to the final in Gdańsk.