Lions wide receiver Calvin Johnson, the focal point of the 49ers' secondary this week, did not practice today with a foot injury. Johnson played throughout Detroit's Week 1 game against the Rams - he had six catches for 111 yards - and reports out of Detroit today said he did not appear to be seriously injured.
The 49er who will be responsible for emulating Johnson in practice this week will be first-round draft choice A.J. Jenkins. The team's defensive backs said that the 6-5 Johnson is particularly good at jump-ball situations, and Jenkins said that's one of the areas on which he's focusing. "When the ball's in the air, just going up and getting it," he said.
Jenkins and the rest of the scout team got high marks from the 49ers defense after the Packers game. Jenkins played the role of Jordy Nelson while practice squadder Nathan Palmer emulated Greg Jennings. LaMichael James and even safety Michael Thomas stepped in to play Packers receivers, with Thomas playing Randall Cobb.
This week, Palmer is playing the role of Titus Young while Thomas will take some snaps as Stefan Logan. Meanwhile, at 6-0, 192 pounds, Jenkins certainly doesn't have Johnson's size of strength. But it's worth noting that last year Johnson was played by Joe Hastings in the run up to the Lions game and that the 49ers mostly kept the receiver under control. (7-113, no TDs)
In other Lions injury report news, safety Louis Delmas (knee), cornerback Bill Bentley (concussion), linebacker Travis Lewis (quad) and defensive end Lawrence Jackson (calf) did not practice. Defensive tackle Corey Williams (knee) and cornerback Chris Houston (ankle) - who had some interesting things to say about Randy Moss -- were limited in today's practice.
The 49ers will release their practice report later this afternoon. ***UPDATE*** Receiver Ted Ginn (ankle) and running back Brandon Jacobs (knee) continue to rehabilitate on a side field. Both are likely to be on the did-not-participate list later today.
-- Matt Barrows