The first reports from training camp via Twitter came from 49ers beat reporter Cam Inman, who tweeted the absence of San Francisco wide receiver Michael Crabtree. The 49ers pass catcher is entering his 4th season as a pro, and in three years prior has yet to complete a preseason from A to Z.

WR Michael Crabtree (ankle?) absent as 49ers start 2nd practice of training camp. Hasn't played in an exhibition game in his 3yr career

— Cam Inman (@CamInman) July 28, 2012

Sacramento Bee writer Matt Barrows confirmed Crabtree's absence in his blog.

The plan is for Michael Crabtree to play an integral role as the split end receiver in 2012, and because of that, this bit of news is probably nothing to overreact to -- the 49ers keeping him out is likely a precautionary move while it's still early in the preseason and guys are still acclimating. The 49ers have not released anything official about the alleged injury; all we know is that Crabtree hobbled off the field on Friday under his own will, with what appeared to be a bothered ankle.

This page will act as an open thread for training camp today while practice is underway.