Arsenal are open to signing a new left-back during the January transfer window, according to reports from The Express. 

The Gunners recently allowed Sead Kolasinac to return to former club Schalke on loan for the rest of the season, meaning Kieran Tierney is the only left-footed full-back remaining in Mikel Arteta's first-team squad. 

Ainsley Maitland-Niles and Cedric Soares are no strangers to playing on that side of the defence but they're both more suited to right-back than left-back, while Maitland-Niles arguably isn't a full-back at all. 

Arteta discussed the situation in his press conference on Thursday morning.

As quoted by The Express, he said "With the departure of Kola, we are a little bit short with left-footed full-backs at the moment.

"We know we can use Ainsley there, we can use Bukayo there and we can use Cedric - who has played in that position - so we have some options. 

"A natural option to Kieran? Obviously, we don't. But we can adapt.

And while not explicitly saying Arsenal are looking to sign another No.3, he did hint that someone could arrive before the winter deadline after being asked about addressing the issue via the transfer market. 

"That means that the option is open and we will look to see what is available," responded the Gunners gaffer.

GIVEMESPORT's Christy Malyan says...

The impact of Tierney's recent absence won't have gone unnoticed by Arteta, with Arsenal failing to net in a scoreless draw against Crystal Palace while the Scotland international was sidelined through injury. 

Tellingly, it was the only match Tierney missed in a run of five Premier League games for Arsenal which otherwise included four victories, as they struggled to create chances against the Eagles - who actually had more attempts on goal than their Emirates hosts.

The Daily Mail and Evening Standard both honed in on Tierney's absence in their post-match analysis, citing how instrumental he's become to the Gunners' attack. 

It's certainly not unheard of in the modern game for full-backs to have that level of influence over their team, but the real lesson to be learned from the Palace draw was how lopsided Arsenal are without the former Celtic star.

With Arteta continuing to deploy right-footed striker Pierre-Emerick Aubameyang on the left wing, Tierney is Arsenal's ultimate source of width down that flank. Soares and Maitland-Niles, in contrast, have to shift onto their right foot to play the ball, which inevitably narrows Arsenal's attack. 

Of course, Bukayo Saka could play there if necessary, but that would require moving the Arsenal player with their third-most Premier League goal involvements this season into a defensive position.

And the unfortunate reality is that Tierney's no stranger on prolonged absences through injury - they have been a recurring theme throughout his club career - so it makes sense for the Gunners to bring in a naturally left-footed understudy. 

Whether they can find the right player before the January transfer window slams shut, however, remains to be seen.