49ers rookie quarterback Colin Kaepernick threw to teammates at player-only workouts in the San Jose area this week. Kaepernick first joined Wednesday's practice, but The Sacramento Bee said Friday's passing session marked his most intense activity yet since undergoing a procedure on his left leg after the 49ers selected him in the second round of last month's draft. He is the second 49ers rookie to work out with veterans after receiver Ronald Johnson, a sixth-round pick, practiced with teammates for 10 days soon after the draft.