Japan may be without two defenders selected for the World Cup soccer finals in Qatar after Yuta Nakayama's club ruled him out for the rest of the season with an injured Achilles tendon, and Takehiro Tomiyasu left his game on Thursday hurt.
Ten minutes after he entered Arsenal's Europe League 1-0 group stage win over Zurich, Tomiyasu sat down on the pitch. Medical staff appeared to be concerned with his right thigh. He was then taken off as a precaution.
"We don't know. He has had a muscular issue and had to come off because we don't want to take any risks," Arsenal manager Mikel Arteta told BT Sport. "But we will assess him in the next 48 hours and decide what is best to do next."
Both Nakayama and Tomiyasu were named in Japan's 26-man squad Tuesday for the tournament beginning Nov. 20.
Huddersfield defender Nakayama damaged his Achilles tendon at the end of the first half in Wednesday's 2-0 loss at home to Sunderland in the second-tier Championship. The 25-year-old will undergo surgery.
"We are all devastated that Yuta will be unable to join up with Japan for the 2022 FIFA World Cup, which is an experience he had completely earned," Huddersfield coach Mark Fotheringham said in comments released on the club's official website.
Nakayama was playing his first season in England since departing Dutch side Zwolle.
A player on the final list for the World Cup may only be replaced in the event of serious injury or illness up to 24 hours before the start of his team's first match.