The news comes as a severe blow to England - already lacking the injured pair of Sol Campbell and Ledley King - with Terry missing the World Cup qualifiers against Wales and Northern Ireland.
However, even more worryingly, the England coach suggested that the 24-year-old may not even recover in time for the final ties of the campaign, against Austria and Poland, in October.
"We will have to see if he is ready for the October games because the doctors say he is out for at least four weeks with a knee injury," Eriksson said.
If the prognosis on the injury which Terry picked up playing against Denmark is correct, and it appears he has strained ligaments, the effect on Chelsea could be even more dramatic, with their captain set to miss three Premiership matches and two Champions' League ties. Those fixtures include two against Liverpool, both at Anfield.
In Terry's absence Eriksson, who last night called Fulham's Zat Knight into his squad, is likely to select Jamie Carragher as Rio Ferdinand's central defensive partner which increases the likelihood of Phil Neville playing at right-back in place of his suspended brother, Gary, who also has a groin injury.
Eriksson also commented wryly that there has been "a lot of talk" about the riches he has in defence. "But that will only give me a problem when they are all fit," he said. "It's good to have a lot of them because we need it."
There was fulsome praise for Carragher, who will earn his 19th cap, with Eriksson saying the 27-year-old's display in the Champions' League final in Istanbul was "incredible". "I think he had cramp all over but he did not leave the pitch," he said. "He has improved a lot in the last years, even technically. He's a good passer."
Eriksson did, however, pass over Carragher's performance in the débâcle in Copenhagen. "Second half, if I should talk individually, I would slaughter all of them," Eriksson said. "I would prefer not to talk about one player. It was a collective collapse." As it is he conceded that both David James, who he had spoken to on Sunday evening, and Glen Johnson, who, it appears, he did not speak to, did pay the price with their omission.
Eriksson also revealed that he had sat the England squad down and shown them a video of the 4-1 defeat to Denmark. "They looked at it, but I don't think they liked it," he said. "We had examples in the first half when we played very well. At least we played well, I think, not very well. In the second half it was the opposite."
Eriksson said that he had talked "before and after" showing the match video, highlighting errors. "And then I asked them if they wanted to say something," he said. Did they? "They were silent," Eriksson, who once more stated that there would "never" be a repeat of that performance, said. Little wonder, although it is disappointing that the players could not find something to say.
Eriksson has refreshed his squad slightly with the inclusion of Stephen Warnock and Luke Young and the retention of Darren Bent, while Steven Gerrard, who trained on his own because of a thigh strain, David Beckham, who has a sore foot, and goalkeeper Chris Kirkland are all likely to be fit for Saturday's game.
Not in Eriksson's team will be the suspended Michael Owen, but the Swede also spoke expansively yesterday about his delight at the striker's move to Newcastle United.
Eriksson has talked to Owen over the last few days. "I think he wanted to resolve the situation in one way or another and he wanted to come back to England," he said. "What I understood is that he did not want to stay in Spain because he had no idea how many games he would play. He wanted to move and he wants to play in the World Cup, of course. That was the main reason, I suppose."
Eriksson said the arrival of Robinho and Julio Baptista at Real Madrid had sealed Owen's fate. "When he saw that Real were buying new strikers it got him worried," he said. "At the end of the season he sees the World Cup and he was worried he would be playing once every three months."
Such a situation may have even jeopardised Owen's international chances, despite the faith constantly shown in him by Eriksson.
"If he never plays it would have created a huge problem for me," he said. "On the one hand you always want Michael Owen in your team but if he never plays then it is difficult. But now that is not a problem."
Eriksson said that the move to Newcastle would also be a great motivation for Owen. "He wants to prove he's another legend up there," he said. "Like Alan Shearer, Malcolm Macdonald. I think it's a huge challenge for him."Reuse content