Arsenal manager Arsene Wenger revealed Alexis Sanchez has endured a recovery setback and will be out of action for an additional three weeks.
The Chile international picked up a hamstring injury in Arsenal's 1-1 draw with Norwich City on November 29 and has been sidelined since.
Sanchez recently resumed regular training and was expected to return to the match squad for Monday's encounter with Manchester City.
However, the former Barcelona man endured a setback in training prior to Arsenal's 2-1 win and will be unavailable for a few more weeks.
"Alexis has had a setback and will not be available until January 10 or so," Wenger said at a news conference.
"The original plan was for him to start from the bench against City, but he had a setback in training two days ago."
The 27-year-old will consequently miss the Premier League games against Southampton, AFC Bournemouth and Newcastle United, while he is also unlikely to feature in the FA Cup clash with Sunderland.
He could potentially return in the away game at Liverpool on January 13.
Sanchez has been a key figure for Arsenal this campaign, scoring nine goals in 20 appearances in all competitions.
