Mari has joined the Saudi Pro League club from Fiorentina and made a winning debut against Al Nassr yesterday.
Inzaghi said after the 3-1 win: "The management has supported the team at this time, I believe Pablo can help us until Koulibaly returns. He will give us a huge boost in the Asian Champions League.
"Al Hilal is a great team that competes on multiple fronts and in several tournaments."
Al Hilal currently lead the Saudi Pro League table by seven points from second-place Al Nassr.