Chelsea defender Reece James required oxygen on the pitch as he was stretchered off during England's defeat to Chile in the Toulon tournament.
James fell awkwardly 28 minutes into the 2-1 defeat with play delayed for over eight minutes while the 19-year-old received treatment.
After a successful loan spell at Wigan, James was tipped to feature in Chelsea's first-team squad next season with the club under a transfer ban.
The blow for James comes weeks after fellow academy prospects Callum Hudson-Odoi and Ruben Loftus-Cheek both ruptured their Achilles towards the end of last season.
James, who was Chelsea's academy Player of the Year in the 2017/18 season, played in 45 of Wigan's 46 league games last season and was named in the 2018/19 Championship Team of the Season.
England's evening went from bad to worse after conceding two late goals as they finished bottom of their group with three defeats from three.