Born in Lebanon, Al Hajj moved to Sweden and represented them internationally at youth level.
[3] On 14 June 2023, Al Hajj signed for OB in the Danish Superliga ahead of the 2023–24 season.
[4] He scored on his debut for the club on 23 July, the opening matchday of the season, converting a penalty in a 2–2 home draw against Randers.
[5] On transfer deadline day, August 30, 2024, Al Hajj joined English EFL Championship club Plymouth Argyle.
[7] He received his first call-up for the senior national team in a friendly match against Estonia on 12 January 2024.