The sun shone on Wembley, supporters were in mid-season voice, Alex Oxlade-Chamberlain delivered a lovely goal, and Chelsea manager José Mourinho was irritated. In other words, success.
Although we shouldn't draw any definitive conclusions from the match, we can make some inferences to guide our thinking in advance of next Sunday's Premier League opener against West Ham. Here are three things that stuck out:
1. This team can adapt to the occasion
Arsenal showed it knows more than one way to achieve its objectives. As in last season's watershed victory at Manchester City, the Gunners conceded much of the possession to accomplished opponents, rather than taking a more assertive offensive approach. Chelsea had 57 percent possession to Arsenal's 43 percent. (Stats from Opta via whoscored.com.)
Manager Arsène Wenger praised this tactical move, suggesting in his post-match press conference that the players made this adjustment. "They were more concerned with protecting our lead against Chelsea rather than playing attacking football," he said. "We have to accept that, and I don’t think that’s giving up your philosophy, it’s a punctual fact that we wanted to win a game like that. I’m quite proud of that."
It wasn't a physical, rear-guard defense that suggested a huge gap in quality between the sides; Arsenal simply controlled the passing lanes with a midfield line that made the most of the energy of Francis Coquelin and Aaron Ramsey. The setup started out like the 4-1-4-1 that manager Arsène Wenger had introduced early in the 2014-15 campaign, then after Oxlade-Chamberlain's goal it often looked like a 4-4-1-1 with Mesut Özil just behind Theo Walcott.
The personnel is already flexible, too. Santi Cazorla occupied the left of the midfield, a position he hadn't taken up for at least a year, and Ramsey returned to the center of midfield, his preferred spot but not one where he's regularly featured since the middle of last season. Top scorer Alexis will eventually return, and the players will shift again.
Indeed, adaptability -- both in the starting lineups and in the positioning of players in games -- could be a feature of the season. Wenger has the opportunity to vary his selections to fit the opposition because the players at his disposal, in just about every position, are of high quality.
2. This defense looks ready and savvy
Arsenal conceded just one goal in five pre-season matches, as a variety of defenders and goalkeepers, not including last season's eventual first choice David Ospina, shut down several dangerous opponents.
On Sunday, Chelsea managed two shots on target. They had two other real opportunities, Ramires's first-half header and Eden Hazard's rushed sky job in the second half, but Arsenal's efforts rendered Chelsea's offense largely ineffective. The midfield's work in the passing lanes stymied Cesc Fabregas, and when Chelsea did reach the spaces just outside the penalty area, where they were most dangerous last season, Arsenal crowded the space and blocked any progress.
Longer approaches were handled by Arsenal center-half Laurent Koscielny. He seemed in top form, shepherding Chelsea's front men and attending to any danger. Koscielny made 16 clearances and won four aerial duels, both top figures on the team.
With Koscielny, his central defensive partner Per Mertesacker, and goalkeeper Petr Cech, Arsenal have an experienced, knowledgeable defensive core. That's a strong foundation for a run at the Premier League title.
3. Arsenal didn't act friendly
This was an exhibition that Arsenal came to win. From the kickoff, the Gunners asserted themselves and did not shirk the physical, psychological, or tactical contests inherent in facing a Mourinho team.
That willingness became especially evident late in the second half. Wenger's substitutions were designed to shore up the defense: the more robust Olivier Giroud for Theo Walcott, deep-lying midfielder Mikel Arteta for playmaker Özil, and fullback Kieran Gibbs for Oxlade-Chamberlain. All three made an impact, with Giroud and Gibbs threatening the Chelsea goal and Arteta throwing himself into challenges, particularly with Chelsea substitute Radamel Falcao.
Also noteworthy was left back Nacho Monreal's canny professionalism. Twice in the first half, he got mixed up with Chelsea's Gary Cahill, once resulting in a bloody nose and then sending Cahill into teammate Branislav Ivanovic right at the Chelsea post. Later, Monreal outmaneuvered Falcao (admittedly not a move with a high degree of difficulty) to draw a foul that eased the pressure, and he made a late clearance to kill even more time.
Applying this savvy and effort in a so-called friendly shows how ready this team is for the season ahead. Given Arsenal's talent, that application can put Arsenal in position to defeat just about any opponent. In close matches against top sides, they're required. Add a moment of brilliance, like Sunday's from Oxlade-Chamberlain, and you've got a recipe for success.