England's Raheem Sterling, Fabian Delph and Jordan Henderson out
Raheem Sterling, Fabian Delph and Jordan Henderson have become the latest withdrawals from England's injury-hit squad.
Gareth Southgate's men kick off their World Cup preparations with Wembley friendlies against Germany and Brazil on Friday and next Tuesday.
Tottenham's Dele Alli, Harry Kane and Harry Winks have already withdrawn from the initial 25-man squad, with England receiving three further setbacks on Tuesday.
"Manchester City duo Raheem Sterling and Fabian Delph have returned to their club after being ruled out of England's forthcoming fixtures," a statement from the Football Association read.
"Liverpool's Jordan Henderson will also miss out on the back-to-back games against Germany and Brazil at Wembley Stadium through injury."
Henderson had been due to arrive at St George's Park later in the week after missing Liverpool's win against West Ham on Saturday with a thigh problem.
City winger Sterling is out with a back complaint and clubmate Delph -- waiting for his first England cap since November 2015 -- injured his calf towards the end of Sunday's win over Arsenal.
Alli, Kane and Winks had already pulled out with injury issues, with Southgate bringing in Michael Keane and Jake Livermore in response.
It appears more faces will be drafted in by the England boss ahead of Friday's friendly against Germany, with the FA announcing that a further squad update would be issued in due course.
Chelsea defender Gary Cahill, who was assessed by his club's medical team after Sunday's 1-0 defeat of Manchester United, will take his place among Southgate's 21-man group for training on Tuesday.
Meanwhile, England will step out in navy rather than their traditional white home strip in Friday's game against Germany.
It will be just the third time England have been able to wear the away Nike kit since its launch in March -- and the first time they have worn an away kit at Wembley since Egypt visited in 2010.
An FA spokesperson said: "The Wembley crowd will have the opportunity to see England in action in the Three Lions' popular midnight navy away kit when they take on Germany.
"Due to kit clashes in recent away fixtures, the senior men have been limited to just two opportunities to wear their change strip.
"The forthcoming back-to-back internationals will now give England chance to showcase their away kit before returning to their traditional white home colours for the visit of Brazil on Tuesday Nov. 14."
England were unable to wear the away kit in recent matches at Scotland and France due to kit clashes, while UEFA judged it to clash with Lithuania's green shorts in last month's World Cup qualifier in Vilnius.
Press Association Sport reports this was a decision taken by the FA rather than Nike, with the governing body mindful of providing value for money for those that have bought the away strip.