Coach Wade Phillips said Wednesday that Jones, who was injured early in the 20-13 loss at Pittsburgh, has a "herniated disk, maybe two" and will definitely miss Sunday's game against the New York Giants.
"Our people don't think it's career-threatening or anything else that he would have to be operated [on] or anything like that," Phillips said. "But it is something that might put him out this year."
However, NFL.com, citing a league source, reported Wednesday that the injury could threaten Jones' career.
Jones was scheduled to be evaluated by another doctor Thursday.
"The prognosis wasn't good for him playing this year, from our people," Phillips said. "They're going to see if maybe they can re-evaluate in a few weeks or they'll say you're not going to play this year. That's what we're looking at."
Jones was hurt in the first quarter Sunday when he fell on top of his muffed punt, getting caught in a scramble for the loose ball. After several players fell on him, Jones was pulled from the pile awkwardly by a Pittsburgh player. But Jones played the rest of the game.
It was Jones' first game back after a six-game suspension, the second time he has been banned by commissioner Roger Goodell for off-field issues.
Jones was not in the locker room Wednesday when it was open to reporters and not available for comment.
Jones Out for the Year?
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