Arsenal midfielder Thomas Partey will have a scan on an ankle injury suffered in Sunday’s 2-1 pre-season defeat to Chelsea.
Partey limped off during the first half following a tackle by Blues midfielder Ruben Loftus-Cheek.
“At the moment it’s not looking good because he was in pain and he could not continue which, for Thomas, is pretty unusual,” said manager Mikel Arteta.
Arsenal travel to Brentford in their Premier League opener on August 13.
Tammy Abraham scored the winner for Chelsea at Emirates Stadium, pouncing on Hector Bellerin’s loose pass before firing home from just inside the area with 18 minutes left.
Granit Xhaka’s header had brought Arsenal level just three minutes earlier, cancelling out Kai Havertz’s first-half opener.
Arteta’s side thought they had levelled late on when Joe Willock’s shot hit the underside of the bar and appeared to bounce over the line, but goalline technology was not in use and the goal was not given.