FIFA Worldcup Mexico vs South Africa (Group A)The 2026 FIFA World Cup is finally under way, with co-hosts Mexico opening the biggest tournament in football history against South Africa at a packed Estadio Azteca in Mexico City.With the World Cup expanding to 48 teams and 104 matches for the first time, all eyes are on El Tri as they begin their Group A campaign against a South African side making their first appearance at the tournament since hosting it in 2010.The match also carries two major individual storylines. Veteran goalkeeper Guillermo Ochoa has officially become the first player ever to be named in six different FIFA World Cup squads, while 17-year-old midfielder Gilberto Mora arrives as the youngest player at the entire 2026 World Cup.Mexico line-up and formationJavier Aguirre has opted for a 4-3-3 system as Mexico look to dominate possession and dictate the tempo from the opening whistle.Goalkeeper: Raúl RangelRight-back: Israel ReyesCentre-back: César MontesCentre-back: Johan VásquezLeft-back: Jesús GallardoDefensive midfield: Érik LiraCentral midfield: Álvaro FidalgoCentral midfield: Brian GutiérrezRight wing: Roberto AlvaradoStriker: Raúl JiménezLeft wing: Julián QuiñonesMexico's shape is designed to be aggressive and front-footed. Israel Reyes and Jesús Gallardo are expected to push high from the full-back positions, while Érik Lira anchors midfield and allows Álvaro Fidalgo and Brian Gutiérrez greater freedom to create chances between the lines.In attack, Roberto Alvarado and Julián Quiñones will provide width around central striker Raúl Jiménez, who leads the line as Mexico's primary goalscoring threat.Among the notable substitutes are Santiago Giménez, captain Edson Álvarez, Alexis Vega, Gilberto Mora and Guillermo Ochoa.South Africa line-up and formationSouth Africa manager Hugo Broos has selected a more conservative 5-3-2 formation, aiming to frustrate Mexico and strike on the counter-attack.Goalkeeper: Ronwen Williams (captain)Right wing-back: Khuliso MudauCentre-back: Nkosinathi SibisiCentre-back: Ime OkonCentre-back: Mbekezeli MbokaziLeft wing-back: Aubrey ModibaCentral midfield: Teboho MokoenaCentral midfield: Siphephelo SitholeCentral midfield: Jayden AdamsStriker: Lyle FosterStriker: Iqraam RaynersThe five-man defence is expected to sit compactly in front of goalkeeper Ronwen Williams, with wing-backs Khuliso Mudau and Aubrey Modiba tasked with balancing defensive duties and quick transitions.In midfield, Teboho Mokoena, Siphephelo Sithole and Jayden Adams will attempt to crowd out Mexico's creative players, while forwards Lyle Foster and Iqraam Rayners remain the main outlets for counter-attacks.Is Guillermo Ochoa playing?Not from the start. Despite becoming the first footballer in history to be included in six FIFA World Cup squads, the 40-year-old goalkeeper begins Mexico's opening match on the bench.Aguirre has selected Raúl "Tala" Rangel as his first-choice goalkeeper for the tournament opener, meaning Ochoa will have to wait for a potential appearance later in the competition.FILE - Mexico's goalkeeper Guillermo Ochoa plays a ball during a training session ahead of a friendly soccer match against Portugal in Mexico City, Thursday, March 26, 2026. (AP Photo/Marco Ugarte, File)Even without taking to the pitch, Ochoa has already reached a historic milestone. The veteran goalkeeper has now been included in Mexico's World Cup squads in 2006, 2010, 2014, 2018, 2022 and 2026.Ahead of the tournament, Ochoa also confirmed that he plans to retire from international football once Mexico's World Cup campaign comes to an end.Is Gilberto Mora playing?The youngest player at the 2026 World Cup is not in Mexico's starting XI, but he is available among the substitutes and is widely expected to feature at some stage.At just 17 years old, Mora arrives at the tournament as one of world football's most exciting prospects. He already holds several remarkable records, including becoming Mexico's youngest senior international and the youngest player of any nationality to win a senior international tournament after helping Mexico lift the Concacaf Gold Cup at the age of 16 years and 265 days.Mexico's Gilberto Mora and teammates warm up during a training in Mexico City, Wednesday, June 10, 2026, ahead of their opening match against South Africa at the FIFA World Cup. (AP Photo/Fernando Llano)Aguirre has regularly used Mora as an impact substitute in recent matches, including friendlies against Serbia and Australia, and the teenager could again be called upon if Mexico need creativity and energy during the second half.Should he step onto the pitch against South Africa, Mora would become the youngest Mexican ever to play in a FIFA World Cup match.Mexico begin as favouritesMexico enter the tournament in encouraging form after winning all three of their pre-World Cup warm-up matches.Aguirre's side scored eight goals and conceded just once during that run, helping establish them as favourites to progress from a Group A that also includes South Korea and Czechia.South Africa's preparations have been less convincing. Hugo Broos' side arrive without a victory in their previous five matches and are still searching for a first-ever World Cup opening-match win after defeats to France in 1998 and draws against Paraguay in 2002 and Mexico in 2010.Sixteen years after sharing a 1-1 draw with Mexico in the opening match of the 2010 World Cup, the two nations meet again on football's biggest stage, this time with a place in the expanded knockout rounds firmly in their sights.