Friday provided a bounty of news at the wide receiver position, starting with Steve Johnson, who left Friday's practice early, and was diagnosed with a strained left hamstring shortly thereafter. It's unclear if the injury is expected to threaten his Week 1 availability, so hopefully more information will come out over the weekend. Robert Woods, T.J. Graham, Da'Rick Rogers, and Marquise Goodwin could all potentially see an uptick in first-team training camp snaps while Johnson is sidelined.
The 49ers have signed Austin Collie, who figures to immediately enter the competition for playing time. Collie is best known for his extensive concussion history, but it was a ruptured patellar tendon that kept him off the field in 2012. Collie, A.J. Jenkins (hamstring), Quinton Patton, Kyle Williams, and eventually Mario Manningham (knee) will all jockey to replace Michael Crabtree's (Achilles) production.
Mike Wallace (groin) will not play in Sunday's Hall of Fame Game, but it sounds like he's only sitting for precautionary reasons. At this point, there is little reason to doubt Wallace's status for Week 1.
Riley Cooper was excused from team activities Friday but still has a spot on the Philadelphia roster. He recently made news for using a racial slur at a Kenny Chesney concert, and will thus attend counseling instead of practice. The situation is reportedly causing some friction in the locker room, but the Eagles are too high on Cooper to cut the cord, at least at the moment.
Hakeem Nicks (groin) missed practice for the second day in a row but expects to return over the weekend. While his knee seems to be doing just fine following offseason arthroscopic surgery, Nicks' groin ailment looks like the most recent in a long line of nagging injuries. Judging by the severity of the groin injury and the time remaining before Week 1, this shouldn't be a major issue, even after accounting for Nicks' history.
Sidney Rice (knee) has returned from Switzerland and is expected to resume practicing Sunday. He went to Switzerland to have a non-surgical treatment done on his balky left knee, but it sounds like he still has a good chance to suit up for the Seahawks' first preseason game next Thursday. Rice is generally expected to be the team's top receiving option while Percy Harvin (hip) is out.
Speaking of Seattle wide receivers, Early Doucet signed a one-year agreement with the Seahawks on Friday. Doucet spent the first five seasons of his career in Arizona, accumulating 1,491 yards and seven touchdowns over 54 games with the Cardinals. It isn't entirely crazy to think that Doucet could challenge Doug Baldwin for playing time, but Sidney Rice and Golden Tate should be safe.