Now is the time to fill the gaps in your knowledge ahead of the big kick-off - even some gaps you didn't know were there.

It's the best and worst, the biggest and smallest, the most and least of the 2018 World Cup.

The heaviest and lightest players

Inui floats like a butterfly

Proof that you can't take World Cup newcomers lightly comes in the form of Roman Torres, the Panama defender and, at 99kg, the heaviest player taking part in the tournament.
At the other end of the scale comes Takashi Inui. The Japan midfielder, who has been based in Europe for seven years and recently joined Real Betis, weighs 59kg.

The tallest and shortest players

Kalinic, sitting down to fit in frame

One keeper you're unlikely to see lobbed in Russia is Croatia's Lovre Kalinic. That's mainly because he's unlikely to play, given Danijel Subasic holds the number one jersey, but it's also because he stands at a towering 201cm tall.

It's a three way tie for the shortest player, with Switzerland's Xherdan Shaqiri, Panama's Alberto Quinterio and Saudi Arabia's Al-Shehri Yahya all at 165cm.

The oldest and youngest squads

Alex Iwobi, one of the fledgling Super Eagles

Who says the Panamanians will go home empty-handed? They've taken three accolades on this page alone. Head coach Herman Dario Gomez has selected the oldest squad at the tournament, with an average age of 29 years and eight months.

Nigeria have the youngest - their players are on average 25 years and 11 months old.

In terms of individual players, Egypt keeper Essam El-Hadary will be a World Cup record breaker should he play aged 45, while the youngest is Australia's very own Daniel Arzani, who is 15 days younger than fellow 19 year-old and Group F nemesis, Kylian Mbappe.