The Catalan giants have travelled to the United States with a 31-man squad, including Lewandowski, who is staying at Camp Nou this summer despite some recent speculation surrounding his future.
Alejandro Balde is a notable inclusion in the squad, with the Spain international recovering from the hamstring problem which made him unavailable in the second half of last season and also at Euro 2024.
However, Pedri, Frenkie de Jong, Gavi, Ronald Araujo and Ansu Fati are absent through injury.
Raphinha and Ilkay Gundogan will join up with the team on Monday, so they could be involved here, while Jules Kounde will arrive on August 1 for the games against Real Madrid and AC Milan.
Pau Victor could make his debut, having arrived at the club on a permanent basis from Girona this summer, while Vitor Roque is in line for a start in the final third of the field.
Julian Araujo, Hector Fort and Pablo Torre could also receive minutes, while Oriol Romeu is in line to start in the middle of midfield.
There will be no Ferran Torres or Lamine Yamal, though, with the attackers on extended breaks after helping Spain win this summer's European Championship, while Fermin Lopez, Pau Cubarsi and Eric Garcia are representing Spain at the Olympics.
Barcelona possible starting lineup: Ter Stegen; J Araujo, I Martinez, Christensen, Fort; Romeu, Gundogan, Torre; Roque, Lewandowski, Victor
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