Mikel Arteta oversaw the Gunners' worst ever league campaign last season and the club is on course to do even worse this season - only Europa League success will do.
Emery's men are surely assured of a top-seven standing in La Liga, and given his personal affiliations with Arsenal, the Yellow Submarine's vocal leader will do everything in his power to make his return to the Emirates a memorable one.
Here, SPORTbible takes a look at everything you need to know ahead of the big game.
How to watch Arsenal vs Villarreal
Arsenal vs Villarreal is scheduled for an 8pm (BST) kick-off on Thursday, May 6.
It will be televised on BT Sport.
BT Sport subscribers will also be able to watch the match online via the website or BT Sport app.
Arsenal vs Villarreal predictions and betting odds
As of late, Arsenal's home form has been dismal and are lucky to even be in with a chance of reaching the final after a disastrous opening hour in the first leg last week.
Villarreal have won their last four Europa League games away from home without shipping a single goal, and they have only failed to progress in one of their last 16 European ties when winning the first leg.
Emery has more than one incentive to steer Villarreal into the showpiece event, as the visiting boss not only has his European reputation to maintain, but also a sense of personal pride as he seeks to dump his former employers out of the tournament.
Arguably, Arsenal should not even be in with a chance of progressing to the final, but Arteta will aim to galvanise his troops and plenty of his big names are well-rested.
Arsenal are 17/20 to win, with Villarreal priced at 3/1 to come away with the victory. A draw is priced at 11/4.
Odds are correct at the time of publication and are, as always, subject to change.
Arsenal team news and injuries
David Luiz was taken off at Newcastle United with a suspected hamstring problem, and Arteta admitted that the centre-back's injury did not look good, so Rob Holding is sure to return to the defence as Gabriel Magalhaes hopes to keep his spot over Pablo Mari.
Mohamed Elneny should earn a start alongside Thomas Partey in midfield with Dani Ceballos suspended, while Calum Chambers, Emile Smith Rowe, Saka and Pepe should all earn recalls to the starting lineup.
Villarreal news and injuries
Spurs loanee Juan Foyth impressed on the right-hand side in the first leg before being forced off with a hamstring issue, and he joins Vicente Iborra in the visitors' treatment room, but Emery has no fresh concerns from the weekend.