From Selhurst Park - It was not quite as bad as when he was dragged off after 34 minutes against Nottingham Forest in January but Nuno Tavares' performance as Arsenal were played off the park by Crystal Palace on Monday night will have been even more concerning for Mikel Arteta.
Right from the outset, it was clear that the 22-year-old, drafted in for the injured Kieran Tierney, was extremely uncomfortable.
Even when pitted against Jordan Ayew – starting his first Palace game since February – Tavares was manic in his defending, flaying his limbs around almost at random as his opponents streamed past him. Positionally, things were equally suspect.
The low watermark of his defensive display was the part he played in Palace's opening goal. While he was not the only Arsenal player at fault here, with the usually flawless Gabriel retracting his head like a shy tortoise at exactly the wrong time, Tavares should have and could have done much more to prevent Joachim Andersen no-look heading the ball into goalscorer Jean-Philippe Mateta's path.
Unfortunately for the youngster his struggles were not confined to his own half either. Whenever he ventured forward, his passes rarely found their mark with one inadvertently kick-starting one of many dangerous Palace counter-attacks. In addition, not a single one of his four long balls forward found their mark.
It was distressing to watch a player who has shown real flashes of promise labour so badly again, and it was little surprise when he was withdrawn for Gabriel Martinelli at the break.
After the game, Arteta claimed that the change was tactical and denied assertions that another premature substitution would affect the player's confidence.
"Today it was just a tactical reason. How we could attack and control much better in that position. I’m sorry that it was Nuno again but we had to do it," he told his press conference.
Despite these claims, it is clear that a second Tavares horrorshow leaves Arteta with a huge decision to make at left-back for the rest of the campaign. Reports suggest that Tierney's injury is a season-ender, and Arsenal's failure to recruit in January has left them short in many areas – defence included.
After Tavares was taken off, Granit Xhaka was shifted over to the left side of the back four. This coincided with Arsenal looking a bit more comfortable without the ball, though Palace's less aggressive press was also a reason for this.
Another option in the long-term would be shifting Cedric Soares or Takehiro Tomiyasu – when he returns – over to the opposite side. All of these solutions have pros and cons which will likely be discussed intensely over the coming days and weeks.
The crux of the matter is this, though. Arteta must get his left-back dilemma right with rivals Tottenham – who remain above Arsenal in fourth after this result – hitting their stride at exactly the right time. It's a problem that could end up defining their season.
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