The Arsenal forward had been the subject of some brutal treatment during his side’s Premier League win over Aston Villa on Saturday, although his absence at St George’s Park is not believed to be linked to either that or Covid-19.
Saka has quickly established himself as one of England’s key players, winning 14 caps since making his international debut in October 2020.
Gareth Southgate has already had to deal with a number of dropouts to the squad he named last week with Arsenal teammate Aaron Ramsdale one of four players to withdraw through injury.
Trent Alexander-Arnold, Reece James and Tammy Abraham did the same with Tyrick Mitchell, Kyle Walker-Peters, Sam Johnstone and Ollie Watkins coming in as replacements.
Johnstone could also be replaced by Southampton’s Fraser Forster after the West Brom custodian missed training with a hip injury.
England host Switzerland at Wembley on Saturday before Ivory Coast on Tuesday.