Iran will play Tahiti and Russia in Group B on Wednesday and Thursday respectively.
The Asian champion had seven different players scoring as it ran riot with an 8-1 thumping of the USA in the last match of the night.
Mohammad Moradi opened the scoring in the very first minute and then added a second midway to be the only one from his team with a brace, while the other goals came from his teammates Amir Hossein Akbari, Mohammad Ahmadzadeh, Mustafa Kiani, Moslem Mesigar, Mohammad Masoumizadeh and Ali Mirshekari as Iran led 8-0 by the end of the second period.
Gabriel Silveira pulled a goal back for the American team.
Group A consists of the UAE (host), Brazil, Egypt and Spain.
The tournament, which is organized by the Dubai Sports Council (DSC) and Beach Soccer Worldwide (BSWW), got underway in Dubai on November 6 and will finish on November 10.