Morgan Gibbs-White and Keane Lewis-Potter have pulled out of the England Under-21s squad to face Italy and Germany.
Nottingham Forest midfielder Gibbs-White and Brentford forward Lewis-Potter will remain with their clubs for assessment and treatment.
Their withdrawals means Tyler Morton has been called up by boss Lee Carsley for the first time.
The Liverpool midfielder, on loan at Blackburn, has three caps for the Under-20s.
The Young Lions are preparing for friendlies against Italy in Pescara on Thursday and Germany in Sheffield next Tuesday.
Carsley said: “It was really important we had two tier one teams to play against. I wouldn’t say qualifying is easy – it definitely didn’t feel it – but there is so much difference between the qualifying campaign and the tournament.
“With the players we have got we need to test ourselves. Finding that balance for the players who aren’t playing that much and the ones who are playing a lot.
“Myself and the staff have spent the last two or three months watching all the best opposition, Holland, Portugal, Spain, Germany, Italy to see where we’re at.
“We’re ranked sixth and I’ve used that as motivation because you want to be around the top three at least.”
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