Mikel Arteta got his second Premier League win as Arsenal manager, but Gary Breen believes that they still have significant defensive problems.
Speaking after commentating on their 4-0 win over Newcastle, Breen highlighted the frailties that he believes might undermine any late-stage push for the Champions League places.
"Newcastle had chances - Joelinton in the first half made a run to the near past where he should have really scored, but didn't hit the target.
"Arteta will highlight the positives of two clean sheets on the bounce, but the reality is Rodriguez should have scored for Burnley and Newcastle should have scored today.
"As much as they have improved, that is not a back four that you can forward with."
In particular, Breen focused on Shkodran Mustafi as someone prone to mistakes.
"Arteta has tried to reintegrate Mustafi back into the team - he is a whole-hearted player but he makes mistakes.
"Ceballos has been placed on the right-hand side to give Mustafi a pass, and the one time he wasn't there Mustafi passed it into midfield, lost it and Newcastle could have scored.
"That is the problem with this Arsenal squad is that there are so many individual errors."
But Arteta brought in defenders in the January transfer window, and Breen is excited by those coming in.
"[Pablo Mari] is someone that Arteta wanted to bring in as he was with him at Manchester City when he was younger.
"Arsenal fans might look at his CV and think 'hold on, he's playing second division in Spain..' but Arteta's requirement is someone that can play out from the back.
"He is a left-footer, got a great switch of play in him and he is commanding. The worry with Mari is his pace - he is not particularly quick - particularly given the high line that Arteta likes to play.
"These are improvements. It was no surprise that as soon as the transfer window opened that he brought in two defenders.
"I like Cedric at right-back. He will provide competition for Bellerin [where Lichsteiner could not.]"