France are preparing for their first World Cup match since leaving South Africa in disgrace four years ago following a player strike and a group-stage exit.
Didier Deschamps' inexperienced squad needs to perform on the sport's biggest stage to win back supporters and is expected to beat Honduras on Sunday, which only compounds the pressure.
Some of the favorites have had a tough time in the first few days in Brazil, with defending champions Spain thrashed 5-1 by Netherlands and Costa Rica upsetting Uruguay, semifinalists four years ago.
Lionel Messi will be in action on Sunday when Argentina open against Bosnia-Herzegovina in Group F. In the other match on day four in Brazil, Switzerland are aiming to live up to their ranking when they take on Ecuador in Group E.
Things to watch for Sunday:
FRENCH PLANNING FOR A RENAISSANCE: France has had an on-off run at the last four World Cups, reaching the finals twice (champions in 1998 and runners-up in 2006) and going out in the group stage twice without winning a match (2002 and '10). If the pattern continues, it'll be a good month for Les Bleus in Brazil.
With only a handful of players remaining from 2010, there's a new energy and enthusiasm. Coach Didier Deschamps concedes there's extraordinary pressure in the opening matches - France haven't won their first match in the last three World Cups - and he's taking a cautious approach with his younger players.
Paul Pogba, 21, is one of France's best young prospects, and 23-year-old winger Antoine Griezmann is a contender to start.
Real Madrid striker Karim Benzema should lead from the front against a physically abrasive Honduran team.
Honduras coach Luis Suarez says his team is capable of causing some upsets, and could even be "the Cinderella of our group."
Defender Emilio Izaguirre and captain and goalkeeper Noel Valladares hold the key to keeping France at bay.
DAVID vs GOLIATH: Bosnia-Herzegovina, playing in its first World Cup, opens against two-time champion Argentina.
Argentina has an abundance of proven scorers, so coach Alejandro Sabella has to settle on how to utilize Sergio Aguero, Ezequiel Lavezzi and Gonzalo Higuain in an attacking formation with Messi.
The 26-year-old Messi didn't make a big mark on the 2010 World Cup. But, after getting into scoring form for Argentina in the qualifiers, the Barcelona forward is preparing for something special in Brazil.
Bosnia coach Safet Susic promised to maintain the attacking strategy that helped his team qualify for Brazil, and didn't want to tinker with his tactics to "sacrifice a player just to man-mark Messi."
The Bosnian strike force includes Vedad Ibisevic and Manchester City striker Edin Dzeko, who scored 10 of the Bosnian team's 30 goals in qualifying and is nicknamed "The Diamond."
SWITZERLAND'S GOALS: The Swiss have two main goals as they open their Group E campaign against Ecuador: 1. Score. 2. Live up to their ranking.
After attracting criticism for scoring just four goals in four games at the 2006 World Cup and only one in three games in 2010, Switzerland overhauled its squad with a group of young dynamic players.
Unbeaten in World Cup qualifying, the Swiss earned a seeding at the World Cup by moving up to No. 6 in the FIFA rankings.
Coach Ottmar Hitzfeld, in an understated way, explained the change: "We are a bit more creative going forward."
Xherdan Shaqiri is the playmaker, while midfielder Granit Xhaka and striker Josip Drmic, both 21, are important to the attacking system.
Ecuador dedicated its qualifying campaign to former striker Christian Benitez, who died suddenly of a congenital heart ailment in July at age 27. Felipe Caicedo is now the first-choice striker and is likely to wear the No. 11 jersey that was briefly retired after Benitez died.
Ecuador defender Fricson Erazo said this week: "Christian is very much in our minds and our hearts and that has made us stronger."