Serbia and Switzerland are expected to vie for second place, having both finished top of their respective groups in qualifying. Cameroon should not be discounted as contenders for a berth in the knockout phase after a third-place showing at the Africa Cup of Nations in February.
Here is a breakdown of the four teams in Group G.
Brazil have not lifted the Jules Rimet trophy since 2002, when a Ronaldo-inspired team defeated Germany 2-0 in Yokohama.
But the five-time world champions are deservedly among the favorites here after a qualifying campaign that included 14 wins, three draws and not a single defeat. The team's only blemish in the 2020s so far is the Copa America final defeat to Argentina at Rio's Maracana stadium in July last year.
Manager Adenor Leonardo Bacchi, better known as Tite, has an embarrassment of riches at his disposal with no apparent weakness, except perhaps for the absence of a world-class center forward. But that is not really a problem, given an abundance of versatile attacking options and the fluid nature of Tite's set-up that lends itself to using Richarilson or Gabriel Jesus as a false nine.
Tite has announced he will step down after the tournament and he - along with 216 million football-mad Brazilians - will not be satisfied with anything less than a triumph in Lusail on December 18.
Key player: Neymar
The Paris Saint-Germain forward will again be Brazil's primary attacking threat and enters the tournament in sublime form, having scored 15 goals and provided 12 assists in 19 games for the French club this season.
The 30-year-old has netted 75 times in 121 appearances for his country and looks set to break Pele's all-time Brazil record of 77 goals in this tournament.
Neymar's role with Brazil has changed markedly since the 2014 and 2018 World Cups when he was deployed as a left winger. The former Barcelona star is now used in a deeper, more central role, where he can showcase all of his skill and ingenuity to not only score goals but create them for his teammates.
One to watch: Bruno Guimaraes
Guimaraes has just eight Brazil caps to his name but is already shaping up as a star of the future. The Newcastle United midfielder has shown an impressive ability to play either in a holding midfield position or as an attacking playmaker.
Whether he is used off the bench or as a starter, the 24-year-old is set to play an important role for Brazil in Qatar.
Cameroon qualified the hard way with an extra-time goal in the second leg of their playoff against Algeria. But Rigobert Song's men proved they will not be out of their depth by finishing third at this year's Africa Cup of Nations on home soil. The Indomitable Lions have had mixed results under Song, who has overseen two wins, three losses and a draw since replacing Toni Conceicao as manager in February.
Key player: Eric Maxim Choupo-Moting
The forward has been a more-than-handy attacking option for Bayern Munich since his arrival from Paris Saint-Germain on a free transfer in October 2020. Despite often starting as a substitute, Choupo-Moting has netted 28 goals and provided nine assists in 73 matches. After a frustrating start to the current season because of a groin injury, the 33-year-old has scored 10 times in 15 appearances across all competitions this term.
One to watch: Souaibou Marou
Song surprised many by including 21-year-old striker Souaibou Marou in his 26-man squad. A return of eight goals in 26 matches for Cameroonian club Coton Sport FC is hardly awe-inspiring, but the team's lack of attacking depth might mean Marou has a role to play in Qatar.
Dragan Stojkovic's team earned a place in Qatar by going undefeated in qualifying and finishing top of their group, three points ahead of second-placed Portugal.
They have not progressed beyond the group stage since France 98 but there is a feeling the long wait for a return to the last 16 could end here despite a difficult group.
A central midfield pairing of Sergej Milinkovic-Savic and Nemanja Gudelj combined with an attack led by Aleksandar Mitrovic and Dusan Vlahovic will prove a headache for Serbia's rivals. There is, however, a question mark over the team's defense, highlighted by a 3-0 defeat to Denmark in March.
Key player: Aleksandar Mitrovic
Serbia's all-time leading scorer was a key member of the Fulham side that earned promotion to the Premier League last season, netting 43 times in 44 outings. His appetite for goals has not diminished in the Premier League with nine goals in 12 top-flight appearances for the London club in 2022-23.
Mitrovic has also been in prolific form at international level. The 28-year-old was the top scorer in Europe's Group A World Cup qualifiers with eight goals, eclipsing Cristiano Ronaldo, who netted six times for Portugal.
One to watch: Dusan Vlahovic
The 22-year-old has quickly emerged as one of the top young strikers in Europe.
His 49 goals in 108 games for Fiorentina have been followed by 17 in 36 matches since his January move to Juventus. Renowned for his strength, sublime dribbling and deft touch, Vlahovic has already made an impact at international level with eight goals and four assists in 16 matches for his country.
Switzerland were another team to highly impress in qualifying, going unbeaten and finishing top of their group, ahead of Italy, Northern Ireland, Bulgaria and Lithuania.
The Swiss have been a model of consistency in recent years, having reached the last 16 in three of the past four editions of the World Cup.
Their best-ever run in the tournament came in 1934, 1938 and 1954, when they reached the quarterfinals.
Key player: Granit Xhaka
The 30-year-old has been in outstanding form for Arsenal this season, scoring four goals and laying off three assists in 19 appearances across all competitions.
The box-to-box midfielder will be playing in his third World Cup, having been an important member of the 2014 and 2018 campaigns in Brazil and Russia, respectively.
Despite having only turned 30 in September, Xhaka is one of the most experienced players in manager Murat Yakin's squad. He has been capped 106 times for Switzerland since making his international debut as an 18-year-old, scoring 12 goals and providing 10 assists.
One to watch: Noah Okafor
With two goals in eight international matches, Okafor has hardly set the world alight since making his debut for Switzerland in 2018. But the 22-year-old has grown in confidence in recent months, netting 10 times in 21 outings for RB Salzburg this season, including seven goals in the Bundesliga.
In Qatar, he is likely to prove a vital component of an attack that includes former Liverpool winger Xherdan Shaqiri and Monaco striker Breel Embolo.