For the first time in 35 years, Arsenal have conceded at least 50 Premier League goals in consecutive seasons.
The Gunners were held to a 1-1 draw against Brighton on Sunday, leaving them fifth in the table and all but ruled out of a top-four finish in the league.
With just one game left in the season, Unai Emery's team have conceded a goal less than the 51 they let slip by in the English top-flight in Arsene Wenger's final year in charge.
They could also end up finishing in the same sixth-place position as Wenger's last team, with sixth-placed Manchester United sitting just a point behind the Gunners heading into the final week.
The north London club's defence has had a difficult campaign. While new goalkeeper Bernd Leno took time to settle in with his new team, captain Laurent Koscielny missed the first four months of the campaign through injury.
Meanwhile, Shkodran Mustafi and Sokratis Papastathopoulos have faced criticism for their performances in the area that has plagued the team for some time.
The last time the Gunners went two seasons in a row conceding as many goals was in 1982-83 and 83-84.
The club have been urged by fans and former stars to address the back line in the next transfer market, with Lee Dixon highlighting the team's defence as a big weakness.
The ex-Gunners full-back told BBC Sport this week: “One of the most disappointing things about Arsenal over the past few months is that, defensively, they are not getting any better.
“They are still making the same awful mistakes and Emery is still chopping and changing from a three to a four at the back, which can't be helping matters.
“He is obviously not happy with what he is seeing and trying to juggle the players to find the right defensive combination.
“I think there will be some major movement in that area in the summer because he realises it is one of the major issues for this team, and will by know by now which players are not good enough."
Meanwhile, Charlie Nicholas believes their defence looks more like that of a team fighting for survival in the top-flight rather than one pushing for a place in the Champions League.
Nicholas said on Friday: "Emery has done a remarkable job with a bottom-six Premier League defence.
"He has made mistakes, but who wouldn't make mistakes with this defence?"
He added: "Shkodran Mustafi has been a waste of £42m which is the biggest bug for me. Sead Kolasinac and Nacho Monreal are left wing-backs, while Sokratis Papastathopoulos lacks pace.
"The reality is, Emery needs four or five defenders and that is a concern as that is an overhaul. I have faith in Emery though as he knows exactly what he needs and what he must do in order to make this happen.