The 30-year-old is believed to have picked up the knock in training on Thursday with Ghanaian FA releasing a statement on Saturday ruling him out of the upcoming international break.
Neither the club or manager Mikel Arteta have placed a real timeframe on his return.
‘I don’t know,’ Arteta said of his midfielder. ‘Unfortunately he got an injury in training and it doesn’t look good, we need some more tests, we believe he’s going to be out for weeks.’
‘We think it’s a groin but can be something in between.’
Arsenal’s medical team expect Partey to miss at least six weeks, according to the Mail, with the club likely to take a cautious approach with his return given his injury history.
That absence will see him miss Premier League games against Arsenal, the north London derby against Tottenham, Bournemouth and Manchester City although he could be back in time for the visit to Chelsea on 21 October.
Partey would also miss Champions League games against PSV Eindhoven and Lens in that run, along with the EFL Cup third round tie away to Brentford.
The Ghana international started Arsenal’s first three games of the new season in a new inverted right-back role. Arteta was forced to tweak his system in his absence on Sunday with Ben White starting on the right and Gabriel Magalhaes returning to the side to partner William Saliba at centre-half.
The Gunners fell behind on Sunday afternoon after Marcus Rashford’s opener but responded a minute later through an equaliser from Martin Odegaard.
Alejandro Garnacho saw his effort ruled out for offside on 87 minutes with Declan Rice scoring five minutes into injury time to give the hosts a dramatic lead.
Gabriel Jesus added another as Arsenal sealed a huge win heading into the international break.
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