Arsenal's bid to win the Premier League could suffer a major setback following reports Kai Havertz is set to be ruled out for the remainder of the season.
The German forward sustained an injury during the club's warm-weather training camp in Dubai and was due to face further tests on the club's arrival back in England.
The Athletic reported on Wednesday that 25-year-old Havertz had suffered a torn hamstring and could miss the rest of the current campaign.
Arsenal, however, have yet to comment on the extent of Havertz's injury.
His potential long-term absence would though compound the problems confronting Gunners boss Mikel Arteta after Arsenal were unable to bolster their attack during the recent January transfer window.
The London club failed in an attempt to sign Ollie Watkins from Premier League rivals Aston Villa.
Havertz was set to lead Arsenal's line for the rest of the season, with Arteta even saying it was possible the Germany international would have to play every game.
Gabriel Jesus is already out for the season after he suffered an anterior cruciate ligament injury last month, while Bukayo Saka has been absent since December, although there are hopes the England international could return next month.
Gabriel Martinelli, meanwhile, is also sidelined after he was forced off injured during Arsenal's League Cup second-leg semifinal defeat at Newcastle last week.
All these absences leave the Gunners with only three recognised forward players in Leandro Trossard, Raheem Sterling and Ethan Nwaneri.
Arteta may well speak about Havertz – who has scored 15 goals in 34 appearances this season – on Friday when he holds a pre-match press conference to preview the Gunners' league game away to Leicester.
Arsenal are presently second in the Premier League, six points behind leaders Liverpool but having played a game more, as they attempt to become champions of England for the first time in 21 years.