The Brazilian, who last month joined the former Asian champions for 90 million euros from Paris Saint-Germain, was introduced in the 64th minute for compatriot Michael and set up Malcom to score Al Hilal's fourth in the 83rd minute.
Aleksandar Mitrovic had put Al Hilal in front with a 30th-minute penalty before goals from Yassir Al-Shahrani and Nasser Al-Dawsari gave the league leaders a comfortable advantage.
Fans jeered as Al Hilal captain Salem Al-Dawsari opted to take an 87th-minute penalty while Neymar watched on, the Saudi Arabia winger converting before adding his side's sixth goal in injury time.
Neymar, who surpassed Pele's record as Brazil's leading scorer when he netted twice in last Friday's 5-1 win over Bolivia, had not played for Al Hilal since moving to Saudi Arabia due to an ankle injury.
