The Tottenham Hotspur defender King suffered an abductor muscle tear in his groin just after the kick-off between England and USA.
He was replaced at half-time by Liverpool defender Jamie Carragher after complaining of feeling a tightness in the muscle.
John Terry told the England bench of the problem right after skipper Steven Gerrard"s fourth-minute goal.
King battled on till half time before being replaced by Jamie Carragher, The Sun reports.
King"s injury is another blow to coach Fabio Capello, who lost centre-back and captain Rio Ferdinand a week before the 2010 World Cup started.
Putting a brave face, Capello said: “We have three other central defenders, Carragher, Michael Dawson and Matthew Upson. I hope we have no more injuries. The problem is not the injuries. The problem is only the result of the game."