They may have taken their sweet time as Manchester City, Liverpool, Chelsea and Manchester United bolstered their squads, but in one fell swoop, Arsenal have eclipsed their rivals with the signing of the summer, Alexis Sanchez.
Getting the Chilean's signature is massive for three reasons:
1) It is Arsenal's second marquee signing in consecutive transfer windows after Mesut Ozil in August 2013.
Before Ozil things were gloomy at the club, from Patrick Vieira all the way to Robin van Persie, Arsenal lost key players at the beginning of every season as trophy droughts and an uncompetitive salary drove away their best players.
Therefore, when Arsenal signed Ozil it signified a massive change in policy, one where Arsenal could compete with the very best in the transfer market. Ozil did not have the best of seasons with Arsenal, but he had a placebo effect on the playing staff and on fans. The Emirates suddenly became a cauldron full of vigour and this spurred the club to win their first title in almost a decade.
If Sanchez has even half the psychological impact Ozil had on Arsenal, it will be enough to put Arsenal in contention for the Premier League title - something they were doing last season until injury derailed the tilt by March.
2) Sanchez gives Arsenal options they never had before
Aside from the unquantifiable, Sanchez's signing has eradicated the one weakness Arsenal had in their attack - a lack of pace. No longer will Arsenal fans fret when Theo Walcott is inevitably injured for several months, they now have a better and more reliable forward in their disposal.
Sanchez also gives Arsenal more flexibility; instead of arrogantly sticking to a high backline that proved suicidal against Chelsea, Liverpool and Manchester City, with Sanchez, Walcott, Joel Campbell and Oxlade Chamberlain all capable of switching between striker and winger, Arsenal can now sit back in the knowledge they can spring from defence to attack in no time. Although it has yet to be proven, on paper Arsenal's counter attack is now on par with Liverpool's and Real Madrid's as the best in Europe.
If this does turn out to be the case, Sanchez could bring out the very best in Mesut Ozil. Ozil is a player who craves space to thread his famous through balls. Last season he was stifled as the likes of Cazorla, Rosicky and Giroud suffocated him by continually dropping deep to receive the ball.
3) It has made Liverpool and Manchester United look small in comparison
Sanchez has done more than strengthen Arsenal, it has weakened Liverpool and made both them and Manchester United look bad. Aside from Carlos Tevez, Sanchez is the closest you can get to a Luis Suarez like-for-like replacement in world football. The fact the runners-up of the Premier League could not secure his transfer when a) they really wanted him; b) Barcelona favoured a Sanchez move to Liverpool, suggests people are putting the success the Merseyside club enjoyed last season largely down to Suarez. If that is indeed the case, Liverpool will struggle to replace the forward as their only perceived world class player has gone and Arsenal have done their bit in exposing the frailties in Liverpool's reputation in world football, and henceforth weakening them.
As for Manchester United, while they weren't linked with Sanchez, they have been linked with Toni Kroos and Cesc Fabregas - two world class midfielders. Toni Kroos was tipped to join Manchester United, well that is until Kroos spoke up and vehemently rejected any interest in signing for the club - he has since been naughtily flirting with Real Madrid - a slap in the face for United if ever their was one.
As for Fabregas, he is now a Chelsea player, but only after Arsenal rejected the opportunity to sign him. Both this season and in the last Manchester United were heavily linked with the player, only for Barcelona and the player to reject their bid, leaving them with no choice but to buy out Ander Herrea's contract clause - 12 months after they felt to do so would be extortionate.
By getting Sanchez, Arsenal have shown they currently enjoy a bigger reputation in football than the two traditional giants of the English game, Liverpool and Manchester United - who would have said that 12 months ago?