England boss Fabio Capello will assess John Terry on Sunday and Monday before a decision is made whether the skipper can face Belarus next week.
Terry's back injury rules him out of this weekend's clash against Kazakhstan - Rio Ferdinand will take the armband at Wembley - and he now faces a race to fit for the following World Cup qualifier.
Capello said: "I don't know if he will be back for Belarus. It depends on his back.
"If he can train a bit on the day after the (Kazakhstan) game and Monday, it is possible. If not, it is not possible to play because there are other players, good substitutes for him."
Matthew Upson, Joleon Lescott and Wes Brown are in contention to deputise at centre-back for Terry against Kazakhstan, with England wanting to build on their famous win in Croatia that put them in control of their group.
"We have 23 players. We have substitutes and I'm sure the substitute for John Terry will play very well," Capello added.
"I'm happy about the performance against Croatia but it was only three points. We have to win again."
Fans have turned on their own team at Wembley in previous matches but Capello expects them to give his side a positive reaction.
"I hope the crowd helps us. If it is not possible to score goals early, we need patience," he said.
"I remember the old Wembley atmosphere, when the crowd helped the team. When we played here, after 20 minutes we could have problems, but I think that the next game the crowd will help us. I'm sure, 100%."
Capello's task has not been made any easier by Kazakhstan changing manager and dropping players - meaning it is a step into the unknown for England.
"I know only four players," Capello said. "They have moved players from the Under-21s and I have one video about these players.
"It's difficult, it's better when you know everything about your opponents."