Phil Foden, Cole Palmer and Ollie Watkins have withdrawn from the England squad for their upcoming Nations League fixtures.
Manchester City forward Foden, who was recently named PFA Player of the Year, was called up by interim England boss Lee Carsley, but did not join up with the squad because of illness.
Chelsea forward Palmer and Aston Villa striker Watkins both reported for duty at St George's Park, but have returned to their respective clubs "to continue their rehabilitation from ongoing issues", said the Football Association.
England face the Republic of Ireland in Dublin on Saturday, 7 September before hosting Finland at Wembley three days later.
The games will be their first since they lost to Spain in the final of Euro 2024 on 14 July.
Gareth Southgate resigned soon after, with under-21s boss Carsley appointed interim manager on 9 August.
Naming his squad for the upcoming Nations League games, he handed call-ups to Angel Gomes, Tino Livramento, Morgan Gibbs-White and Noni Madueke.
Lille winger Gomes, Newcastle defender Livramento, Nottingham Forest midfielder Gibbs-White and Chelsea forward Madueke all played for Carsley during his time as England Under-21 manager.
Manchester City playmaker Jack Grealish, who was cut from England's preliminary Euro 2024 squad, was recalled as well as Manchester United defender Harry Maguire.