But a team source said he should play in Sunday's game against the Jacksonville Jaguars.
Newman was an observer during practices this week due to his health, but on Friday morning told coach Wade Phillips he felt a lot better.
Newman suffered the injury in Monday night's loss to the New York Giants while making an interception. Newman told reporters he heard something pop but played through pain.
He received a pain killing shot during the game.
It's expected Newman will be watched closely during pregame warmups to make sure no problems arise.
The Cowboys have three cornerbacks on the 53-man roster and if Newman goes down, safety Alan Ball, a corner in college, would move to cornerback in some situations.
Calvin Watkins covers the Cowboys for ESPNDallas.com.