Venezuela 2-0 Germany
Venezuela began their U20 World Cup campaign with a shock 2-0 win over Germany at the Daejeon World Cup Stadium.
Ronaldo Pena opened the scoring after 51 minutes, before Sergio Cordova sealed the victory three minutes later.
Argentina 0-3 England
England proved too strong for Argentina in their campaign opener, as they romped to a 3-0 win over Argentina.
Dominic Calvert-Lewin, Adam Armstrong and Chelsea's Dominic Solanke were on target for England.
Argentina finished the game with 10 men when Lautaro Martinez was shown a straight red card after the Video Referee caught the player hitting Fikayo Tomori with an elbow.
Vanuatu 2-3 Mexico
Mexico began their campaign with a thrilling 3-2 win over debutants, Vanuatu on Saturday afternoon.
Kevin Magana and Ronaldo Cisneros put the Mexicans two goals up before Vanuatu hit back through Bong Kalo and Ronaldo Wilkins in the second half.
However, Mexico secured the victory in stoppage time courtesy of a strike from Edson Alvarez.
South Korea 3-0 Guinea
South Korea got their campaign off to a winning start after claiming a 3-0 win over Guinea on Saturday afternoon.
Lee Seungwoo, Lee Minhyeok and Paik Seungho were on target for the South Koreans.