Harry Winks and Mason Holgate have been forced to withdraw from the England U21 squad due to injury.
Tottenham midfielder Winks has returned to his club for further assessment on an ankle problem, while Everton defender Holgate has withdrawn from the squad in order to undergo minor ankle surgery.
Both players will now miss the upcoming games against Romania on March 24 and Ukraine on March 27.
Aidy Boothroyd's side face Romania in a friendly at Molineux on Saturday, before they host Ukraine in a European Qualifier at Bramall Lane the following Tuesday.
The Young Lions sit top of qualifying group four, five points clear of joint-second placed Ukraine and the Netherlands.