Following the death of Queen Elizabeth II last week, the US embassy in London has been closed, meaning the pair have had to fly home to Argetina before processing their applications to visit the United States from there.
However, Romero and Martinez are expected to be available in time, meaning the former should partner Nicolas Otamendi at the heart of the defence, with Emiliano Martinez, Nahuel Molina and Nicolas Tagliafico joining them in the defensive hub of the team.
Should Romero or Martinez not be considered for selection, though, Udinese's Nehuen Perez is on standby to make his international debut having been called up for the second time by Lionel Scaloni.
Likewise, Benfica's Enzo Fernandez could feature for La Albiceleste for the first time, but Leandro Paredes, Rodrigo De Paul and Giovani Lo Celso are expected to form an industrious and technically accomplished midfield triumvirate from the outset.
Ahead of them, it is difficult to see beyond Lionel Messi, Lautaro Martinez and Angel Di Maria starting, even if Paulo Dybala's and Julian Alvarez's decent form for their new clubs Roma and Manchester City respectively will have given Scanoli plenty to think about.
Argentina possible starting lineup: Martinez; Molina, Romero, Otamendi, Tagliafico; De Paul, Paredes, Lo Celso; Messi, Martinez, Di Maria