Getting their Group C campaign under way at Miami's Hard Rock Stadium, Benfica and Boca Juniors will play their Club World Cup opener on Monday.
One of Europe's most historic sides take on an iconic South American institution, as both battle with underdogs Auckland City and mighty Bayern Munich for a place in the knockout phase.
Match preview
Having taken something of a backdoor route into FIFA's revamped and expanded Club World Cup competition, Benfica will aim to take full advantage and go deep into the latter stages.
Restrictions on how many teams from one nation can enter meant that the Portuguese giants were selected, due to having the seventh-best record among eligible clubs in UEFA's four-year ranking.
Twice recent quarter-finalists in the UEFA Champions League, the Eagles also made an impact on Europe's top tournament last season, beating Atletico Madrid 4-0, plus posting wins away to Monaco, Red Star Belgrade and Juventus.
Only Barcelona eventually ended their run in the last 16, before Bruno Lage's side narrowly lost out to city rivals Sporting Lisbon in the league - and then the cup final, which they lost after extra time.
While they finished with just the Taca da Liga to show for their efforts, Benfica scored 84 goals in the Primeira Liga and will have plenty of firepower available in the United States.
Though this is their first appearance at the Club World Cup, Portugal's most successful team previously participated in the 1961 and 1962 Intercontinental Cup as European champions, losing in 1961 and again one year later.
Finally claiming the globe's top trophy may seem a long shot this summer, but escaping Group C is Benfica's minimum ambition.
Boca Juniors made just one appearance in the Club World Cup during its previous format - in 2007, they lost 4-2 in the final to AC Milan - but they did lift the old Intercontinental Cup a joint-record three times.
Renowned for their Azul y Oro jerseys and inimitable 'chocolate box' stadium, Boca are back as the second-best eligible team in CONMEBOL's four-year rankings.
Many of those qualification points came from their run to the 2023 Copa Libertadores final, which they lost to Fluminense, as they have since failed dismally to make any imprint on South America's top competition.
After failing to even qualify in 2024, they suffered a humbling exit to Peru's Alianza Lima in the qualification playoffs this year - a far cry from their most recent continental triumph of six so far, which came some 18 years ago.
Recently eliminated from Argentina's Torneo Apertura by Independiente, Boca parted ways with head coach Fernando Gago, heralding Miguel Angel Russo's third spell at the Buenos Aires club; so there has been plenty of turmoil to deal with before heading to North America.
A squad sprinkled with veterans boasting many years of European experience - most notably, ex-Manchester United quartet Sergio Romero, Marcos Rojo, Edinson Cavani and Ander Herrera - therefore has plenty to prove in Group C.
Boca Juniors form (all competitions): W W L D W L
Benfica form (all competitions): W W W D D L
Team News
Benfica boss Bruno Lage is still without long-term absentees Alexander Bah and Manu Silva, while Swiss striker Zeki Amdouni has not had his purchase clause triggered and will return to parent club Burnley.
Otherwise, the Eagles will have a strong squad available on Monday, with Vangelis Pavlidis set to spearhead their attack: the Greece international scored 19 goals and set up seven in the 2024-25 Primeira Liga.
Playmaker Orkun Kokcu created more chances than any other player in Portugal's top flight (76), also racking up 14 goal involvements last term, and he should feature in midfield.
Meanwhile, vastly experienced Argentine duo Angel Di Maria and club captain Nicolas Otamendi are sure to take a full-blooded approach against their compatriots.
In the absence of another South American stalwart, injured striker Edinson Cavani, Boca Juniors will turn to Miguel Merentiel for inspiration up front - the latter registered six goals and three assists in the 2025 Torneo Apertura.
Peruvian full-back Luis Advincula is short of full fitness and may also miss out, but Ayrton Costa has belatedly been cleared to enter the United States after receiving a temporary visa.
Recently signed on loan from Milan, fellow centre-back Marco Pellegrino should also take a place on Boca's bench; Marcos Rojo and Rodrigo Battaglia are expected to start.
Boca Juniors possible starting lineup: Marchesin; Blondel, Battaglia, Rojo, Blanco; Delgado, Herrera; Zeballos, Palacios, Zenon; Merentiel
Benfica possible starting lineup: Trubin; Araujo, A. Silva, Otamendi, Carreras; Aursnes, Luis, Kokcu; Di Maria, Pavlidis, Akturkoglu
We say: Boca Juniors 1-2 Benfica
Though Benfica are approaching this tournament at the end of a long European season, they should still have enough gas in the tank to beat a below-par Boca side.
Among his fellow veterans, Angel Di Maria can take centre stage at Hard Rock Stadium, helping the Eagles claim three precious points.
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