Jefferson has been out since December, and the 20th-ranked Blue Devils are leaning heavily on a six-man rotation.
Jefferson has shed a protective boot. After Saturday's 88-78 win over NC State, Krzyzewski said a bone in Jefferson's foot has "healed pretty well" and that he is working to "walk properly" without the boot or crutches.
Krzyzewski said Jefferson is also doing rehab work in a pool but said he thinks "it's a while" before Jefferson can return.
Jefferson was the leading returning scorer from last season's NCAA champions. He started the first nine games, averaging 11.4 points and 10.3 rebounds.