[11] In July 2018, it was reported that Al Haj had undergone a trial with Austrian Football Bundesliga side Admira Wacker, with a professional contract expected to be signed.

[13] He also scored a goal against Salam Zgharta in the 2018 Lebanese Elite Cup,[14] which he won after Nejmeh beat Akhaa Ahli Aley 1–0 in the final.

[23] He made his debut on 4 October 2020, in the first matchday of the 2020–21 Lebanese Premier League;[24] Ahed won 3–2, with Al Haj playing 76 minutes.

[24] On 27 May 2021, Al Haj assisted Nour Mansour's header through a corner kick, helping Ahed beat Al-Muharraq of Bahrain 2–1 in the 2021 AFC Cup group stage.

[26] On 31 July 2021, Al Haj sustained an ACL injury during Ahed's 2021 Lebanese Elite Cup final game against his former team Nejmeh.

[citation needed] On 24 April, he scored a penalty against Sahel in the 2022–23 Lebanese FA Cup semi-finals, to help Ahed progress to the final.

[32][33] Al Haj was first called up to the Lebanon senior national team by coach Aleksandar Ilić for a training camp in Bnachii, Zgharta between 19 and 27 September 2022.

[39] Al Haj's father and agent Jamal captained and managed Nejmeh,[4] while his older brother Youssef also plays football.