Joleon Lescott and Paul Robinson are out of the England squad, with Gary Cahill and Joe Hart called up in their place.
Fabio Capello's side are up against Ukraine on Saturday before hosting Belarus at Wembley in their final World Cup qualifiers.
Manchester City defender Lescott sustained a calf injury in Monday night's 1-1 draw with Aston Villa.
And Blackburn goalkeeper Robinson, who was beaten six times in Rovers' drubbing by Arsenal at Emirates Stadium on Sunday, has a hip injury.
Bolton centre-back Gary Cahill, who has often been on the fringes of the England squad, has been called up in place of former Everton man Lescott.
Cahill travelled to Kazakhstan in June with the seniors but is yet to make his England debut.
And Hart, who is on loan with Birmingham for the season from City, will replace Robinson to act as cover for David James and Rob Green, with Ben Foster sidelined by a chest injury.
Capello's men are already assured of their place in the 2010 World Cup finals in South Africa having won all eight of their Group Six qualifiers to date.
Hart and Cahill were travelling south to meet up with their team-mates while the rest of the squad were at Arsenal's London Colney complex for training ahead of Saturday's clash in Ukraine.
All 22 players were present for the start of training but Chelsea full-back Ashley Cole and Portsmouth goalkeeper David James returned to the dressing room while the others went through their warm-up routine.