Mamadou Soumaré and Gonzalo Perez Arce led the scoring with six goals for the defending champions at Pavillón Municipal de Deportes in Pontevedra, which is co-hosting the event with Vigo.

Also winning their opening games were Slovenia, who overcame Tunisia 32-25, and Serbia, who edged out Japan 21-19.

In Group B, 2017 bronze medallists France opened with a comprehensive 48-19 victory over Nigeria.

African junior champions Egypt breezed past Australia 44-17 and Sweden, three-times winners of this competition, triumphed 34-28 against South Korea.

Croatia top an embryonic Group B courtesy of a 23-17 win over Kosovo.

Brazil won 35-30 against Portugal, while another tightly-contested battle saw Hungary defeat Bahrain 34-30.

Germany lead the way in Group D following their 43-25 hammering of Argentina, while Denmark – who have been beaten in four of the past five finals – edged out Norway in a 32-31 thriller.

Iceland got off to a winning start with a 26-19 success against Chile.

The top four countries from each group will qualify for the last 16, with Vigo hosting the final on July 28.