MONACO — Striker Folarin Balogun of the United States was unable to participate in training with Monaco on Thursday after sustaining another blow to his recently injured shoulder, casting uncertainty over his availability for the upcoming Champions League clash against his former team, Arsenal.

Balogun had previously missed approximately two months due to this injury, making his return to the field at the end of November.

Having transferred from Arsenal to Monaco in a permanent move last year, Balogun was taken off the pitch after 68 minutes during a 2-1 defeat against Marseille in the French league last week. Monaco’s coach, Adi Hütter, confirmed that the player had taken a hit to his shoulder, and has been experiencing ongoing discomfort since.

“Yesterday he was unable to complete the practice due to pain. He received treatment and stayed inside today,” Hütter informed the media on Thursday, noting the uncertainty regarding Balogun’s recovery in time for Monaco’s league matchup against Toulouse on Saturday.

Earlier in the season, Balogun showcased strong form, scoring in three consecutive matches. He netted a goal as Monaco claimed a 2-1 victory at Rennes on October 5, but soon after sustained an injury. This dislocated shoulder led him to sit out several matches with the U.S. national team.

“There’s definitely some frustration on his part because he has put in significant effort to make his comeback,” Hütter commented. “He engaged in extensive treatment, and now he is feeling pain. Everyone is hopeful that he can return, perhaps by Saturday.”

Originally from New York and raised in London, Balogun joined Monaco on a five-year contract.

Both Arsenal and Monaco find themselves tied with 10 points after completing five matches in the newly structured Champions League, setting the stage for their matchup at the Emirates on Wednesday.