Arsenal winger Theo Walcott has dislocated his shoulder while training with England ahead of Wednesday's friendly against Germany in Berlin.
Walcott was taken to hospital where the shoulder was put back into place.
A decision will be taken on Wednesday morning over when the 19-year-old will fly back to England.
"Our priority is Theo and making him as comfortable as possible before he returns home," said England manager Fabio Capello.
"We are all very disappointed but the important thing is for Theo to travel home and make a quick recovery."
Capello handed Walcott his first competitive start for England in September's World Cup qualifier against Andorra.
He then scored a hat-trick in Croatia and also started against Kazakhstan and Belarus.
The injury is a blow to Capello, who is already without Steven Gerrard, Frank Lampard, Wayne Rooney, Rio Ferdinand, Wes Brown, Joe Cole, Ashley Cole, Emile Heskey and Joe Hart, but it is even worse news for Arsenal manager Arsene Wenger.
I don't see what you gain from this friendly - you can explain a friendly to prepare for an official match but after this there is no international game for four months
Arsene Wenger speaking prior to Walcott's injury on Tuesday
Walcott has been a regular for the Gunners this season and, having seen his team collect just four points from their last four league games, Wenger must do without one of his most potent attacking players.
Last season the Derby midfielder Stephen Pearson was ruled out for a month after suffering the same injury.
Even if Walcott equalled that timescale, he would miss four league games and the rest of Arsenal's Champions League group campaign.
Walcott missed the end of the 2006-07 season after undergoing surgery to repair a problem with his left shoulder, which he also injured during Arsenal's defeat by Stoke this season.
"During tonight's training session Theo Walcott dislocated his right shoulder after falling on the pitch," said an FA statement.
"Arsenal's medical staff were advised of the injury soon after the incident."
Speaking on Tuesday prior to learning of Walcott's injury, Wenger expressed his displeasure at the timing of the international break.
"It is particularly not welcome at the moment because it is at a period where you want your players to recover a little bit," he told the Arsenal website.
"I don't see what you gain from this friendly because there is no game. You can explain a friendly to prepare for an official match but after this there is no international game for four months."
Capello, who can now call upon just four of his likely first-choice line-up, is not angry with the clubs whose players pulled out before the trip to Germany, according to the Football Association.
The FA's Adrian Bevington told BBC Radio 5 Live that Capello "didn't seem to be fuming" and there was "no dispute" over the withdrawals.
Fulham's Jimmy Bullard and Scott Parker of West Ham have been added to the squad as replacements for Gerrard and Lampard.
Captain John Terry, who was struggling with a foot injury, has declared himself fit.
Former skipper David Beckham, who is one cap away from equalling Bobby Moore's tally of 108 caps, has been left out of the squad.
Beckham has not played since Los Angeles Galaxy's season finished on 26 October after they failed to make the Major League Soccer play-offs.
Despite the injuries to Heskey and Rooney, Capello opted not to recall striker Michael Owen, who scored for Newcastle in their draw with Wigan on Saturday.
Terry excited by young England side
Chelsea defender Michael Mancienne - currently on loan at Wolves - was a surprise inclusion in Capello's squad.
Mancienne, who is yet to play for the Chelsea first team, joins uncapped Aston Villa duo Curtis Davies, 23 and Gabriel Agbonlahor, 22, in a youthful England setup.
Germany, meanwhile, are set to hand starts to midfielders Jermaine Jones and Simon Rolfes, in the absence of Michael Ballack and Torsten Frings.
Chelsea's Ballack misses out after having a foot operation, while Frings has been left out to give younger players experience.
Germany have four uncapped players in their squad, in goalkeeper Tim Wiese, defenders Marvin Compper and Marcel Schaefer and midfielder Tobias Weis.
Coach Joachim Low said: "I don't know how it will work yet but I want to give a chance to some or all of them. They're not in the squad by accident."
England squad: Carson, Robinson, James, Bridge, Davies, Johnson, Terry, Lescott, Mancienne, Richards, Upson, Barry, Carrick, Downing, Bullard, Parker, Wright-Phillips, A Young, Agbonlahor, Bent, Crouch, Defoe.
Germany squad: Adler, Wiese, Compper, Friedrich, Hinkel, Mertesacker, Schaefer, Tasci, Westermann, Hitzlsperger, Jones, Marin, Rolfes, Schweinsteiger, Trochowski, Weis, Gomez, Helmes, Klose, Podolski.
6 months ago