Group B gets underway on Friday with a high-stakes game for Morocco and Iran, both very much the group underdogs.
Morocco are appearing in their first World Cup finals since 1998. Made famous as the first African team to reach the knockout stages in 1986, they beat Portugal to secure progress on that occasion, so they'll be hoping it's a good omen to be paired with them again.
Iran have played in two World Cups since Morocco last featured without winning a game. They performed commendably in 2014, drawing with Nigeria and giving Argentina an almighty scare, but despite a strong qualification campaign they are still seen as one of the weakest nations at the tournament.
Expect a very tight affair in St. Petersburg.
Both sides have managed to maintain their qualifying form throughout their preparations.
Morocco in particular have been in excellent form, winning four and drawing one of the five games they've played since reaching the tournament. Most notable in that run was a 2-1 win over Serbia in Italy. They've conceded just three goals in those five games, so Iran will find them a tough nut to crack.
Iran have played ten games since qualifying, including three games against other World Cup sides. They beat Panama, drew with Russia and lost to Tunisia, so a bit of a mixed bag. Still, they've won seven of those friendlies and head into the tournament with high confidence.
Hervé Renard is in charge of his fourth African team but this will be his first experience of the World Cup. However, his major tournament record is excellent, having become the first manager to win the Africa Cup of Nations with multiple countries after leading Zambia and Ivory Coast to success in 2011 and 2015 respectively.
The former Cambridge United manager - the second ex-U's boss to manage at the World Cup in the past 20 years - masterminded Morocco to the biggest upset of African qualifying as they topped their group ahead of his former team, Ivory Coast. He's done a great job so far, but the World Cup is a different animal entirely.
By contrast, few managers in Russia have as much World Cup experience as Carlos Quieroz. He led Portugal to the last 16 in 2010 before taking charge of Iran in 2011, but he couldn't lead them past the group stages last time out.
The Netherlands may have failed to qualify for the World Cup, but they will not be without representation. Five of the Morocco squad were born in Holland and they are all in contention to start against Iran. Indeed, 17 of the 23-man squad were born outside of Morocco but qualified to play for the Atlas Lions through dual nationality.
Among the toughest decisions facing Renard is who will lead the line. Khalid Boutaïb has more experience but Ayoub El-Kaabi is the man in form, with two goals and an assist in his last three games. There's also a question over right back. Nordin Amrabat and Achraf Hakimi have filled in there but Nabil Dirar may return despite not playing since March.
Iran have undergone something of a facelift in the last four years. With the exception of the squad's most capped player Ehsan Hajsafi, the team that faces Morocco may be entirely different from the one that kicked off the last World Cup against Nigeria.
Morocco (4-1-4-1): Munir; Hakimi, Benatia, Saiss, Dirar; El Ahmadi; Ziyech, Boussoufa, Belhanda, N Amrabat; El-Kaabi
Iran (4-2-3-1): Beiranvand; Mohammadi, Cheshmi, Khanzadeh, Rezaeian; Shojaei, Hajsafi; Taremi, Ansarifard, Jahanbakhsh; Azmoun
Nobody's expecting a thriller in St. Petersburg between two teams who rely very heavily on their defences. Iran conceded fewer goals than any other side in AFC qualifying and Morocco didn't let in a single goal during their final qualifying group, so both of them know what it takes to shut up shop.
But neither can afford to sit back. With Spain and Portugal to come, winning here is the only chance either side has of reaching the last 16. Can either team maintain their defensive principles while also going in search of a positive result?
If one team can nick the win, it might be Morocco. They have the stronger squad, the better form and perhaps, after 20 years away from the World Cup, more desire. Keep Azmoun quiet, and they keep Iran quiet.
Prediction: Morocco 1-0 Iran