Six matches took place on the opening day in South Korea ©WBSC

Defending champions United States began their pursuit of a record fifth straight title with a comfortable win over South Africa at the Under-18 Baseball World Cup in South Korea.

The US, winners of the last four editions of the World Baseball Softball Confederation event, swept aside South Africa 11-0 in Group B at Gijang-Hyundai Dream Ballpark.

It took only seven innings for the US to record a dominant win as they got their title defence off to the perfect start.

Japan, the last team to beat the US at the Under-18 Baseball World Cup, survived a scare in their Group B opener as they were pushed all the way by Spain.

The Japanese side went 2-0 down early on, but fought back to earn a 4-2 victory to avoid an upset.

Chinese Taipei defeated Panama 4-1 in the other Group B match.

In Group A, Canada thrashed China 17-3, while Nicaragua edged out Australia 3-2 and South Korea were on the right side of a 5-4 scoreline in their clash with the Netherlands.

A further six matches will take place tomorrow.