Mikel Arteta has admitted he is unsure as to how soon Kieran Tierney will return for Arsenal while conceding the Gunners missed him during the dull 0-0 draw against Crystal Palace at the Emirates on Thursday evening.
Tierney has become a vital fixture in the north Londoners backline this term, in defence, as well as bombing forward along the left flank.
A muscle issue kept him out of the Gunners drab stalement with the Eagles - with Arsenal far less effective offensively.
Speaking to Sky Sports after the match, Arteta provided an update on Tierney, saying: "I don't know [when he will be back]. He is going to have an MRI scan and we'll see how he is."
On how much Arsenal missed him against Palace, he added: "He's a real threat and the way we are playing and the way we attack on that left-side, he's a really important player.
"We didn't have him, he's injured, and we have to find other solutions."