The Gunners impressed in a 3-0 victory over Manchester City on Sunday, but Arsene Wenger's side still needs a defensive midfielder and another center back.
On Sunday, 35,000 Gunners supporters bounced out of Wembley convinced they have the squad to genuinely challenge for the Premier League title this season following the 3-0 victory over champion Manchester City in the Community Shield.
Alexis Sanchez has arrived to spice up the attack, Aaron Ramsey has picked up where he left off last season and Mesut Ozil returns this summer as a World Cup winner with a year of Premier League experience under his belt.
The addition of fitness expert Shad Forsythe to the backroom team has also offered encouragement that the Gunners could avoid the annual injury crisis that usually corresponds with a drop in form.
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In the first half against City, Arsenal played with the attacking skill, technique and speed that the fans want to see. Sanchez provided the pace that has been missing since Theo Walcott's knee injury in January, and the midfielders interchanged with slick passing and movement with which City failed to cope.
They were up against an almost unrecognizable City defense. Joe Hart, Pablo Zabaleta, Vincent Kompany and Martin Demichelis will all expect to start when Manuel Pellegrini's side faces Newcastle next week.
But Arsenal can only beat what is put in front of it and Wenger has built an enviable group of technically gifted attacking players.
And yet there is still something missing.
Arsenal is so close to being able to boast a starting XI as strong as any in the division, but there are still two glaring weaknesses in the team that can be easily addressed.
Mikel Arteta, the new club captain, is a tidy player but not the dynamic and proactive defensive midfielder that Wenger needs in front of his back four.
A player like Morgan Schneiderlin or Sami Khedira would automatically improve the Gunners, providing a screen for the defense, a player to start attacks and offer a base for Sanchez, Ramsey and Co.
Without a genuine defensive-minded midfielder, Arsenal risks getting torn apart against the better sides, which will exploit any space in the final third. The Gunners won only once against the rest of the top four last season and suffered thumping defeats at City, Liverpool and Chelsea.
The money is there for Wenger to spend some 20 million pounds on a new midfielder, just as it is to sign a top-class center back replacement for Thomas Vermaelen.
Mertesacker's late return from the World Cup and the Achilles injury that forced Koscielny out of the Community Shield mean there is a real chance that left back Nacho Monreal could start in central defense in next weekend's opener against Crystal Palace.
That is not good enough for a potential champion with money burning a hole in its pocket.
Calum Chambers looks, potentially, like a very promising addition as both a fullback and central defender. But Wenger should not be depending on a 19-year-old who has only been at the club for a couple of weeks.
Arsenal is so close, particularly with Alexis likely to play as a central striker and Walcott wide on the right. With Ozil supplying the bullets and Ramsey storming forward from midfield, it seems like the Gunners have almost the perfect attacking balance.
Wenger has been stockpiling technically gifted attacking players for years. To make it count, he now needs to fix a problem that's been staring him in the face for years by signing a defensive midfielder and adding center back cover.
If he can do so before the transfer window closes, that first Premier League title since 2004 will become a genuine possibility.