Arsenal midfielder Abou Diaby is facing up to nine months on the sidelines to recover from a knee complaint, the latest in a long line of injuries to have plagued the France international.
Diaby tore the anterior cruciate ligament in his left knee at a training session on Wednesday.
"Following consultations with specialists, Abou will undergo surgery to repair the injury in the near future,'' Arsenal said Thursday. "Abou is expected to be out for around eight to nine months.''
Diaby has been blighted by injuries since joining from Auxerre in 2006, fracturing and dislocating an ankle after four months at the Premier League club. The commanding midfielder made only 27 Premier League appearances during the next two seasons.
He eventually established himself as a regular in Arsenal's midfield, scoring seven times in 40 matches in all competitions in 2010-11.
But he was restricted to only five appearances last season due to a string of injuries, including ankle and calf problems, and has played only 16 games in the current campaign.
The latest problem adds to manager Arsene Wenger's mounting injury problems.
Jack Wilshere is recovering from an ankle problem which has ruled him out since the loss at Tottenham on March 3.
Wenger must also do without forward Theo Walcott against Reading this weekend after he returned home early from England duty with a pelvic injury, while defender Kieran Gibbs is doubtful because of a virus.
Arsenal is fifth in the league, four points behind Tottenham in the fourth Champions League place.