The tourists' will definitely have to go into the second Test without Wales and Ospreys centre Andrew Bishop, who has been ruled out with a broken hand.
Bishop followed Jones off the field at the weekend after a strong performance and will be missed by his side on Saturday. Meanwhile, Jones is awaiting further medical assessment before his fitness for next week's rematch can be determined.
"Andrew has a spiral fracture to the third metacarpal bone in his right hand. The injury is not complex but he is in plaster and will be out of action for the next four weeks," said Wales physiotherapist Mark Davies.
"Stephen has a sore thumb and he has been x-rayed, but the initial results are inconclusive and we are arranging for a further scan to fully determine the extent of the injury."
No replacement will be called in for Bishop with cover at centre provided elsewhere within the squad. A final decision will be made on Jones, and on any potential replacement for the fly-half, over the next 24 hours subject to medical advice.