Manchester United signing Éderson has been named as his replacement.
Wesley, 22, left the pitch in tears after just 15 minutes of the friendly, which served as Brazil's final warm-up before their Group C campaign begins. The scan results confirmed the severity.
The Brazilian Football Confederation issued a statement: "The MRI scan revealed a muscle injury to the adductor muscle in his left thigh. The CBF regrets the injury. Wesley is a player much loved by the squad and will always be considered part of this team as it seeks to win its sixth World Cup title."
Éderson, 26, will join the squad in the United States on Monday. His call-up comes ahead of his scheduled move to Manchester United, where he is expected to complete paperwork formally in early July after the club agreed a £35m fee with Atalanta earlier this month. He won the last of his three Brazil senior caps in March 2025.
Carlo Ancelotti's side open their Group C campaign against Morocco on Saturday in New York, before facing Haiti in Philadelphia on June 19 and Scotland in Miami on June 24.