The Cowboys had to remove Spencer from the active/physically unable to perform list to add him to the 53-man roster. He will not play in the Sept. 7 regular-season opener against the San Francisco 49ers, but if he was kept on reserve/PUP, he would have missed the first six games of the season.
On Friday, coach Jason Garrett said he was not sure when Spencer would be able to practice. Spencer, who will play right defensive end, had microfracture surgery on his left knee last fall and has gone through a painstaking rehab process. In the last few weeks, the Cowboys have said Spencer is ahead of schedule on his comeback.
The Cowboys also have rookie defensive end DeMarcus Lawrence on the active roster despite a broken foot. He is likely to be placed on injured reserve with a designation to return. He needs to be on the 53-man roster through Tuesday in order to be placed on the short-term IR. With this designation, he would miss the first eight games of the season but be eligible to practice starting in Week 6.