Iran, who had defeated Argentina 15-13 in its opening match, will play Peru on Tuesday.
Each team plays at least six games throughout the tournament.
In the preliminary stage, the teams in Division 1 will play in two groups of four teams. The teams in Division 2 will play in four groups of three teams.
The round-robin Championships are contested by 20 nations, including the world’s heavy hitting water polo nations Serbia, Spain, Hungary and the US.
The championship started on June 10 in Bucharest/Otopeni, Romania and will finish on June 17.