Arsenal midfielder Emile Smith Rowe has been ruled out of action until December after undergoing an operation on his groin.
The 22-year-old played in 33 of Arsenal's 38 Premier League games last season – only three outfield players featured more regularly – but he has struggled for minutes this term.
Smith Rowe has not started any of league leaders Arsenal's opening seven matches in the competition and has totalled just 48 minutes on the pitch.
He has been struggling with a persistent groin issue, which was aggravated in the 3-1 loss to Manchester United earlier this month, and it was decided he would undergo surgery.
Arsenal confirmed on Thursday that Smith Rowe is facing a long spell on the sidelines, effectively ruling him out until the final fortnight of the year due to the break for the World Cup, a tournament the England international is now certain to miss.
"In recent months, Emile Smith Rowe has been experiencing discomfort in his groin, which has limited his training and match appearances," the club statement read.
"Following a significant setback at our Premier League match against Manchester United at Old Trafford on September 4, and after further specialist consultations and discussions with our medical team, Emile underwent surgery to repair a damaged tendon in his groin.
"This successful surgery took place in London in the past few days and Emile’s rehabilitation programme is already under way. We are hopeful that Emile will return to full training in December.
"Everyone at the club will now be supporting and working hard with Emile to get him back on the pitch as soon as possible."
Smith Rowe has played 86 games for Arsenal in all competitions and has scored 18 times.
The three-cap England international's shot conversion rate of 23.81 is the fourth best of any Premier League player to have scored at least 10 times since the start of last season.
Arsenal return from the international break with a north London derby showdown against Tottenham on Saturday.