World Cup in Qatar: What to know before play starts, including the must-see games, biggest stars — and how it all works.

A last chance for Lionel Messi and Cristiano Ronaldo. Kylian Mbappé back on the biggest stage of all. Brazil bidding for a record-extending sixth title.

One of the most eagerly anticipated World Cups in memory — as much for off-the-field reasons as those on it — begins Sunday in Qatar.

Thirty-two teams, 64 matches, 29 days. The first World Cup in the Middle East.

League play around the world has paused and now soccer’s focus is on Qatar, whose national team opens the tournament with a match against Ecuador.

Here are a few things to watch when group games get going in the smallest country ever to host a World Cup, where some fans will be staying in floating hotels when they head over to take in the action:

Brazil (No. 1 in FIFA ranking). Neymar, Vinícius Júnior and the rest of the flair-filled Selecao are peaking at the right time. Is a first World Cup title since 2002 on the horizon?

Belgium (No. 2). The “Golden Generation” is gradually breaking up but there’s still Kevin De Bruyne leading the Belgian charge. There is a doubt about the fitness of Romelu Lukaku, however.

Argentina (No. 3). No World Cup title since the days of the great Diego Maradona. This will be the first World Cup since his death in November 2020 and Argentina has improved under coach Lionel Scaloni, with Messi still at its core and leading the team on a 35-match unbeaten run.

France (No. 4). The defending champions. Still the country with the most depth to its squad, despite an injury list that includes Paul Pogba and N’Golo Kante. Now with Mbappé AND Karim Benzema leading the attack. No team has retained its World Cup title since Brazil in 1962.

England (No. 5). The team has hit a bad patch of form — winless in six games — but has a strong track record in recent major tournaments. England was a semifinalist at the World Cup in 2018 and a finalist at the European Championship in 2021.

Read up on all 32 teams who will be playing in the World Cup.

Lionel Messi, Argentina. The seven-time world player of the year might have been saving his 35-year-old legs for one last push at a World Cup winner’s medal that, to many, would solidify him as soccer’s greatest player. He is in stellar form for Paris Saint-Germain at the moment.

Cristiano Ronaldo, Portugal. He has won the European Championship but the leading scorer in men’s international soccer hasn’t played in a World Cup final, let alone won one. He’s 37 years old now and no longer first choice at Manchester United — so make the most of him while you can.

Kylian Mbappé, France. The star of the last World Cup at the age of 19 and he is only getting better. The speedy striker could match Brazil great Pelé in being a champion at his first two World Cups.

Kevin De Bruyne, Belgium. Widely regarded as the world’s best midfielder, his driving runs and crossing are among the best sights in soccer. Belgium will be thankful he is arriving in Qatar healthy.

Neymar, Brazil. Often overshadowed by Mbappé and Messi at Paris Saint-Germain, still the main man for Brazil. Watch out for tricks and flicks, and some histrionics, too.

Get ready for a feast of soccer. There are eight groups of four teams, with the top two advancing to the 16-team knockout stage.

There will be four games back-to-back per day — yes, four! — for most of the first two sets of group games, then simultaneous kickoffs for the last two games in each group.

There’ll be no break for the knockout stage, which begins the day after the group stage ends. The first day without soccer comes on Dec. 7 — the 17th day of competition.

Qatar vs. Ecuador, Sunday. The first match of the tournament and always a date to save on the calendar.

Argentina vs. Mexico, Nov. 26. The first of the big continental rivalries in the group stage, with Messi potentially sealing his and Argentina’s spot in the last 16.

Spain vs. Germany, Nov. 27. Surely there can’t have been many bigger group-stage matches than this at a World Cup? Two recent champions, two giants of European and world soccer.

Iran vs. United States, Nov. 29. It has been labeled as “The Mother of All Games Part II.” Just like at the World Cup in 1998, the two countries will meet in the group stage in a politically charged matchup. Diplomatic relations have yet to be restored between the nations since being severed in 1980.

Ghana vs. Uruguay, Dec. 2. Anyone remember the night of July 2, 2010? In the last minute of extra time in a World Cup quarterfinal match between Uruguay and Ghana, Luis Suarez deliberately stopped the ball with his hand on the goalline, got sent off, only for Ghana to miss the penalty and lose in a shootout as Suarez celebrated on the sideline. Revenge would be sweet for Ghana.

Injuries have hit some of the world’s best players ahead of the tournament.

Among those definitely missing are France midfielders Paul Pogba and N’Golo Kante, Germany forward Timo Werner and England defender Reece James.

The following are carrying injuries: Lukaku, South Korea forward Son Heung-min, Senegal forward Sadio Mane and Argentina forward Paulo Dybala.