Arsenal manager Mikel Arteta was presented with plenty of questions by the media on Monday and one of those was focused on the team news.

Takehiro Tomiyasu was left out of the 26-man squad for the pre-season tour of the United States with a knee injury and when pressed on this, Arteta said that it is unbelievable.

The Spanish tactician added that the incident happened in training over the past week and he does not know the extent of the knee injury sustained by the Japan international.

He added that the versatile defender has remained in England as a precaution and he is likely to be assessed in the coming days to find out the extent of the setback.

He told Arsenal.com: "It is unbelievable, because the kid works so hard. He had an incident in training this week and we don't know yet the extent of that [knee] injury but as a precaution we kept him [in England]. We'll see what happens."

The PS30 million-rated star joined the club from Bologna in the summer of 2021. Since his arrival, he has been a fantastic performer in the full-back positions with his strong defensive attributes.

However, the 25-year-old has struggled to stay fit over a prolonged period of time. He was in-and-out of the starting XI due to the same last season and has now suffered another unfortunate setback.

Tomiyasu's preparation for the new campaign will be delayed as a result. He will be behind schedule compared to his teammates and may have to be eased into action by the manager.

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