Once on PUP, a player can't be placed on injured reserve unless he passes his physical, begins practicing and then is injured again. Setterstrom underwent surgery on June 23 for a torn triceps and the recovery period was said to be four to six months, which would be as early as October or as late as December.
At the time of the NFL roster cuts to 75 and then 53 players, the Rams will likely place Setterstrom on reserve/PUP, and he wouldn't count against the roster. However, he would be eligible to begin practicing after the sixth week of the season, which is the week of Oct. 18. There is a 21-day window beginning that week for players to begin practicing. Once that occurs, they can practice another 21 days before the team has to decide whether to activate the player or keep him on PUP.
It had been believed that Setterstrom would be waived/injured and then placed on injured reserve to clear a roster spot for the signing of quarterback Sam Bradford. With this decision, another player will have to go off the roster when Bradford signs.