John Terry trained with England on Monday and looked to have won his battle to be fit for the World Cup double-header against Moldova and Ukraine.
But Chelsea team-mate Ashley Cole was in a race against time to recover for the latter qualifier after being ruled out of Friday's match in Chisinau with an ankle injury.
Blues captain Terry played a full part at England's London Colney base, looking completely untroubled by his recent neck injury as he headed several balls during the session of more than an hour.
Cole earlier became the second player to withdraw from what had been a 24-man squad for Friday's Group H opener, having struggled with an ankle problem since Chelsea's UEFA Super Cup defeat against Atletico Madrid on Friday.
The 31-year-old was set to be reassessed on Sunday to determine whether he would be fit for next Tuesday's home game against Ukraine.
The injury ended Cole's hopes of becoming the first full-back to win 100 England caps during this month's double-header. He is currently on 98 and will have to wait until at least next month to reach his century.
It was unclear on Monday whether his ankle injury was related to the long-standing issue that has needed to be managed after matches for club and country.
England boss Roy Hodgson is unlikely to call up cover, with Leighton Baines and Ryan Bertrand having both been named in the original squad.
Striker Andy Carroll had already been ruled out of both games after suffering a hamstring injury on his West Ham debut on Saturday, while Hodgson was already without Wayne Rooney, who suffered a gashed leg playing for Manchester United before the squad was named.
Sixteen of England's 22 remaining players trained on Monday, with those involved in matches on Sunday restricted to gym work: captain Steven Gerrard, Danny Welbeck, Glen Johnson, Alex Oxlade-Chamberlain, Michael Carrick and Tom Cleverley.