Arsenal have released the following statement relating to the fitness of the club's Japanese international  

Following his substitution during last Thursday’s Europa League match [when Arsenal lost 5-3 on penalties following a 1-1 draw after extra time at the Emirates], subsequent assessments have confirmed that Takehiro Tomiyasu sustained a significant injury to his right knee.

Tomi has had successful surgery in London on Tuesday and will be ruled out for the remainder of this season.

Everyone at the club will now be working hard with Tomi, so he can join pre-season training ahead of next season.