The United States men's water polo team opened up its Olympic tournament with a thrilling two-goal victory over host nation Japan, 15-13.

Japan got out to an early three-goal lead in the first half but the Americans recovered to take the lead by one heading into the fourth quarter. The one-goal lead remained in the final minute, before first-time Olympian Johnny Hooper iced the game with a clutch goal.

Alex Bowen led all scorers for Team USA with five goals on six shots. Seven other Americans contributed goals while goalkeeper Drew Holland contributed nine saves.

Team USA is in search of its first Olympic medal since the Beijing 2008 Olympics.

Elsewhere:

• Italy hammered South Africa 21-2
• Greece came back to top Hungary 10-9
• Montenegro beat Australia 15-10
• Spain held on to defeat Serbia 13-12