The result means Oman will face Bahrain in Thursday's quarter-finals, while Iran is set for blockbuster, win-or-go-home clash against FIFA Beach Soccer World Cup regular Japan.
Iran had started the campaign with a 5-2 win over Iraq on Saturday.
The tournament is being held in Thailand on March 9-17.
The championship also acts as the qualification tournament for Asian teams to the 2019 FIFA Beach Soccer World Cup in Paraguay; the top three teams will qualify.