National selector Geoff Miller has been widely predicted to announce at Lord's on Thursday an unchanged squad for the first Test of a four-match series against the Proteas.
But the squad is set to be for just that match only, allowing Flintoff to be considered for the second Test at Headingley which starts on July 18.
The 30-year-old, who has spent six weeks this season on the sidelines, recently returned to action with Lancashire.
And while England take on Graeme Smith's men at Lord's, Flintoff can expect to be involved in county action against Hampshire at the Rose Bowl.
"It's plain for everybody to see where he's at: the work he has put in has been absolutely fantastic but there is bat form to consider, he will want some runs, and a few more miles in his legs as well," said Miller.
"We have just picked for this first Test match because obviously Fred (Flintoff) is in a situation and there is a chance for us to have another look at that," the former England off-spinner added.
"We are not sure where we are beyond that first Test match."
Flintoff has not played a Test since January 2007, when he was captain of the team beaten in Sydney to condemn England to a 5-0 Ashes whitewash by Australia.
For much of that time he has been sidelined with a left ankle injury. The suspect joint, placed under strain by right-arm quick Flintoff's bowling action, has now been operated on four times.
Meanwhile doubts emerged over England captain Michael Vaughan's fitness this week after the Yorkshire batsman suffered a recurrence of the right knee trouble which forced him out of the 2006/07 Ashes.
However, Yorkshire coach Martyn Moxon said there was "no danger" of Vaughan missing the Test match.
England have played the same XI in their last five Tests, winning four of them, and Miller said: "Consistency, that's the watchword we have preached all the way along, and we have just won two Test series against New Zealand, one away and one at home."
After naming the Test party, Miller will announce England's provisional 30-man squad for September's Champions Trophy tournament in Pakistan.
England's 3-1 one-day series defeat against New Zealand last week, saw them slip to seventh in the International Cricket Council rankings for the 50-over game and the selectors may be tempted to bring in some new names.