Arsenal boss Arsene Wenger has confirmed he will be without Gabriel for the first two months of the new Premier League season due to an ankle injury.
The 25-year-old centre-back sustained the problem in the Gunners' final pre-season outing against Manchester City on Sunday, although he suggested earlier this week it was nothing serious.
Gabriel was expected to start in central defence for Wenger's side this weekend when they kick off the new campaign against Liverpool at the Emirates Stadium.
But the Frenchman conceded on Wednesday that the Brazilian defender will only be available again in October, ruling him out of the league games against the Reds, Leicester, Watford, Southampton, Hull, and Chelsea.
"Gabriel has an ankle problem, and will be out for six to eight weeks," Wenger told the club's official website.
He also said that Per Mertesacker would be sidelined for the next "four to five months" with a knee injury, leaving the north Londoners short of options at the back as Laurent Koscielny is still lacking match fitness having being given extra time off after helping France reach the Euro 2016 final last month.