Arsenal have reportedly made a decision regarding Kieran Tierney's future at the club heading into the January transfer window.

The left-back made his first appearance of the season for the Gunners on Wednesday night as they beat Crystal Palace in the quarter-final of the Carabao Cup. Tierney played 69 minutes in the 3-2 victory at the Emirates Stadium before being replaced by Myles Lewis-Skelly.

However, it seemed that the left-back may have been withdrawn with a potential injury which forced Mikel Arteta to make a change to the Arsenal team.

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Tierney has spent the majority of the season on the sidelines recovering from a hamstring injury he picked up in the summer while featuring for Scotland at the European Championships.

With a little over six months until Tierney's contract is set to expire, there has been speculation about whether or not the left-back has a long-term future with the Gunners. According to The Athletic, though, Arsenal are not planning to activate the one-year option in Tierney's contract.

As a result, the report claims that Arsenal could lose Tierney for free when his contract expires at the end of the season. It's also been reported, though, that the left-back could leave in the January transfer window if a suitable offer is received.

With Tierney injured, Arteta has selected several different options at left-back. Riccardo Calafiori, Jurrien Timber, Oleksandr Zinchenko and Lewis-Skelly have all been used at left-back this season, with Arteta regularly making changes in the position throughout the campaign.

From January 1, Tierney will be able to negotiate a pre-contract agreement with clubs outside England over leaving Arsenal for free at the end of the season. It remains to be seen if the Gunners will look to sanction Tierney's exit in January, with the possibility of an injury against Palace likely to put a stop to a move away from the Emirates in the New Year.