The Gunners were only able to get one deal over the line during January after Spanish midfielder Denis Suarez moved to Arsenal on loan from FC Barcelona for the remainder of the season.
Arsenal have conceded 36 times in 25 games in the Premier League this season to highlight their weakness at the back despite Emery recruiting a number of defensive-minded signings last summer.
Indeed, all five of the north London outfit’s summer arrivals were brought in to make them more solid at the back ahead of the new season but the Gunners have struggled to blossom into a cohesive unit.
Arsenal have the worst defensive record of any team in the top six and Emery is facing a real challenge to steer the Gunners to their first top-four finish since Arsene Wenger’s men finished in second place in 2015-16.
Former Arsenal midfielder Petit was critical of Arsenal’s decision to neglect their defence in the January transfer window.
“The frustration level must be very high for Emery, as in only his second transfer window as Arsenal manager he was told he cannot sign anybody,” Petit told Independent.ie.
“You look at the money Manchester United, Liverpool and Manchester City spend and, unless you join them and put the cash on the table to compete for the best players, you are going nowhere.
“Tottenham are not spending money but they are in the position Arsenal were in a few years ago – building a stadium – but there is no excuse for Arsenal now.
“If you sack Arsene Wenger and then say to the guy who replaces him ‘you have no money to spend on new players’, I would ask; what was the point of sacking Wenger in the first place?
“Defensively, Arsenal have not been good enough this season, so I was surprised they did not try to sign defenders in January. But the problems they have will not be solved by signing a player or two.
“Clearly, the defence is a problem. The better teams are getting through them far too easily, and when I hear Emery say he is happy with his defence and he does not need new players in these positions, I’m pretty sure he does not believe this.”
Arsenal signed Bayer Leverkusen goalkeeper Bernd Leno, Borussia Dortmund defender Sokratis Papastathopoulos, Lorient midfielder Matteo Guendouzi, Sampdoria star Lucas Torreira and Juventus veteran Stephan Lichtsteiner last summer.
The Gunners finished in fifth and sixth in the Premier League table in the last two seasons.
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