On the face of it, the advantage looks wafer-thin. Yet 1-0 is rarely an unsatisfactory lead for any side to carry with them into the away match of a two-legged European tie. Villarreal will find it difficult to breach an Arsenal defence with 829 Champions League minutes of clean-sheet football behind it.
Arsenal have had more productive nights during this exhilarating run, but there was still plenty for their followers to be enthused about.
Beginning the game like a house on fire in the last European match ever to be played at Highbury, Arsène Wenger's team made life extremely hazardous for an edgy, twitchy Villarreal. It was a yellow submarine devoid of torpedoes on the night.
The direct, high-energy start whetted appetites that the Spanish visitors could be submerged beneath a cruel sea of goals. Arsenal were doing everything at a blistering pace in the first half, and it seemed to take Villarreal a good quarter of an hour to come to terms with their opponents' speedy approach.
Arsenal had many things going for them by then.
Gilberto was doing an expert snuffing out job on the much-vaunted Juan Riquelme. Emmanuel Eboué and Mathieu Flamini were pushing forward at every opportunity in the manner Wenger likes to see, while Cesc Fabregas was prompting and organising to good effect in the middle, and Thierry Henry was at his usual dashing best.
The Arsenal captain felt certain he had given the home side an 8th minute lead. Austrian assistant referee Egon Bereuter erroneously raised his flag for offside after Robert Pires had threaded the ball through to his compatriot.
I'm not prepared to join the chorus of whistler bashers. Judging whether or not a player is offside can be hard enough with the benefit of multiple frozen replays. Think how difficult it must be in the heat of the moment at real speed.
Villarreal too, had cause to feel robbed, thanks to a ruling (or lack thereof) by an official.
Jose Mari might well have been brought down from behind by Gilberto inside the box. In this case, referee Konrad Plautz, who didn't have the best angle from which to decide, waved play on. On such occasions, it's easy to speculate that Jose Mari's reputation for being something of a penalty hunter, worked to his detriment.
The game's only goal came just minutes before this penalty denial. Henry, whose corner had been nodded away, ran with the ball on the left and found Alexander Hleb. The cutback by the Belarussian was swept home efficiently by Kolo Toure.
Arsenal opted for the prudent approach after the break. Yes, there were moments of adventure, but the prevalent trend was towards less ambitious football.
It's also true that it takes two to tango. Villarreal showed themselves to be less than interested in doing much more than preserving the status quo. A 1-0 defeat, it seemed, was fine by them.
I've watched Manuel Pellegrini's team quite a lot this season, domestically as well as in the Champions League. They can play an awful lot better and more dynamically than this. Pellegrini himself conceded as much in his post-match remarks.
Mind you, the fact that they're only a goal behind, with the home leg still to come, means they certainly can't be written off.
The problem, as I see it for Villarreal is one of being obliged to take the game to Arsenal. They did this successfully at home to an average Inter side in the last round, but it's not their natural disposition.
Besides, Arsenal compared to Inter, are an entirely different proposition for me.
Thierry Henry, Freddie Ljungberg and Jose Antonio Reyes, who'll be back from suspension, will have considerably more freedom at the Madrigal than any Arsenal player enjoyed in the first leg. Villarreal simply can't afford to sit back as they did in London.
The submarine has lost its most experienced Champions League helmsman in Alessio Tacchinardi for the return leg, thanks to his fifth yellow card of the competition. With Gonzalo Rodriguez and Juan Peña again to miss out through injuries, Pellegrini will have more enforced line-up tinkering to contemplate.
Can I envisage Villarreal scoring twice on Tuesday night? It's entirely possible, if Riquelme and Diego Forlan can perform at the high level we've become accustomed to.
However, more likely than the above scenario for my money, is one that has Arsenal nicking a goal on Spanish soil. Under those circumstances, I find it hard to imagine Villarreal scoring three times.
It's not in the bag for the sole remaining English standard bearers yet, but a May journey across the Channel is a step closer to becoming reality.