Saad's identical twin brother, Yasser Al-Mousa, is also a professional footballer.[3] Both of the brothers played for Al-Ettifaq's youth and reserve teams before Yasser's departure in August 2023. Yasser currently plays for First Division side Hajer.
Club career
Al-Mousa began his career at the youth team of Al-Ettifaq. He signed his first professional contract with the club on 3 February 2021.[4] On 15 December 2022, Al-Mousa made his debut for Al-Ettifaq by starting in the 0–0 draw against Damac.[5] On 29 March 2023, he was awarded the Young Player of the Month for his impressive performances in the month of March.[6] On 17 January 2024, Al Mousa joined fellow Pro League side Al-Ittihad on a six-month loan.[7] On 18 February 2024, he made his debut for Al-Ittihad replacing Fawaz Al-Sqoor in the 60th minute in the 2–0 win against Al-Riyadh.[8] On 8 March 2024, Al Mousa scored his first goal for Al-Ittihad in a 2–1 win against Al-Okhdood.[9]
On 4 June 2024, Al-Mousa joined Al-Ittihad on a permanent deal.[10]