Michael Crabtree (foot) participated in on-field activities Monday for the first time in training camp. Crabtree didn't fully practice -- he remains on the active/PUP -- but it was a step in the right direction. Observers spotted Crabtree catching passes in a red sweatshirt and baseball cap, with coach Jim Harbaugh on the throwing end of many of them. Crabtree's status for Week 1 remains questionable.