<P> The opening ceremony took place on Thursday, 14 June 2018, at the Luzhniki Stadium in Moscow, preceding the opening match of the tournament between hosts Russia and Saudi Arabia . </P> <P> Former Brazilian World Cup - winning striker Ronaldo walked out with a child wearing a Russia 2018 shirt . English pop singer Robbie Williams then performed two songs before he and Russian soprano Aida Garifullina performed a duet while other performers emerged, dressed in the flags of all 32 teams and carrying a sign bearing the name of each nation . Dancers were also present . Ronaldo returned with the official match ball of the 2018 World Cup which was sent into space with the International Space Station crew in March and came back to Earth in early June . </P> <P> Competing countries were divided into eight groups of four teams (groups A to H). Teams in each group played one another in a round - robin basis, with the top two teams of each group advancing to the knockout stage . Ten European teams and four South American teams progressed to the knockout stage, together with Japan and Mexico . </P> <P> For the first time since 1938, Germany (reigning champions) did not advance past the first round . For the first time since 1982, no African team progressed to the second round . For the first time, the fair play criteria came into use, when Japan qualified over Senegal due to having received fewer yellow cards . Only one match, France v Denmark, was goalless . Until then there were a record 36 straight games in which at least one goal was scored . </P>

How many games are played per group in the world cup
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