Gerrard and Walker miss England's clash with Chile
The duo sat out training at Arsenal's London Colney training facility on Wednesday morning, but they have not yet been ruled out of England's following game against Germany next Tuesday.
In Gerrard's absence, Frank Lampard is set to captain England on Friday.
Manchester United pair Michael Carrick and Danny Welbeck withdrew from the squad on Tuesday, with United subsequently announcing that midfielder Carrick will be out for up to six weeks with an Achilles injury.
Related England News