Jack Wilshere has compared Arsenal's change in shape to that of the club's Invincibles side of 2003-04.
Arsene Wenger switched to a three-at-the-back shape in the latter stages of last season, breaking away from his long-held four-man backline, which heralded an upturn in fortunes for the Gunners and has been retained this season.
The England international has said that the 3-4-3 formation allows the ball to be played further up the pitch, much like the side that went the entire league season without defeat.
Wilshere told the club's official website: "The boss decided to change the shape last year, it worked well and he's stuck with it. We've improved defensively as a team.
"In that transition when we lose the ball, we want to win it back quickly like the best Arsenal teams over the years.
"The Invincibles were great at it because they'd lose the ball but then win it higher up and we'd be in a dangerous position. That's probably the best change [I have seen]."
The 25-year-old was on loan at Bournemouth during last season and made 27 appearances for the Cherries before a broken leg ended the spell.
Wilshere has made three appearances this season, playing twice in the Europa League campaign.