The 28-year-old suffered a toe infection prior to Euro 2012, while a recurrence of the injury kept the Liverpool defender out of England's 8-0 victory over San Marino on Friday.
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"In the Euros he had a slight toe problem which we had to look after," the Three Lions boss told reporters.
"All of a sudden it has occurred, although not to the same extent. There is no doubt he could have played [against San Marino] - we could even have had him on the bench - but it would have meant an injection and I preferred to continue the treatment so he didn't have to put a boot on.
"We hope it will get better in the next couple of days. If it doesn't it might need an injection but there is no problem.
"It was just a precautionary measure because I felt we had enough players without taking any unnecessary risks."