Sadaoui had a brief spell in the South African top-flight with the now-defunct side that has been renamed Cape Town Spurs ahead of the 2020/21 GladAfrica Championship campaign.
However, he netted three goals in the five games he featured in under then-manager Roger de Sa before joining Miami United FC in the United States.
The Morocco-born talent them embarked on a nomadic journey with clubs in Honduras, Oman and Egypt before an incredible season in the Botola Pro with Mouloudia Oujda.
Sadaoui netted 12 goals and registered three assists 16 starts in the league as he helped them finish fifth to qualify for the Arab Club Champions Cup and second in the Golden Boot race behind Brahim El Bahraoui.
"It's a true honour for me to sign for a big club like this, it's always been my dream to be in a club like this and in an environment with a team that always wants to win titles," the 27-year-old said upon his unveiling.
"Since I was young, my dad took me to a Raja game, I remember telling him that I want to play in this stadium and I'm just very happy to be here."
Sadaoui will be aiming to make his debut for the 2019/20 CAF Champions League semi-finalists when they kickstart their new campaign in Africa on 22 December in the First Round of the competition.