According to Matt Maiocco and this tweet just moments ago:
The 49ers say they will place WR Michael Crabtree on the physically-unable to perform list with a foot injury.
And from Matt Barrows of The Sacramento Bee:
The foot injury that kept Michael Crabtree out of player-run practices in June is more serious than previously believed, and the 49ers' top wideout could miss four to six weeks of training camp and the preseason, according to a source with knowledge of the situation.
The exact nature of the injury is not known and the 49ers did not return calls Thursday night. Crabtree, who had surgery to correct a stress fracture in his left foot early in 2009, reinjured that foot on June 6, the first day of a player-run minicamp. At the time, Morgan said that Crabtree was sore from wearing new cleats on San Jose State's artificial surface playing field.
This could be a huge blow to San Francisco as they prepare for the upcoming season. While Crabtree should be available for Week 1, you have to worry about his conditioning and transition back onto the field. This reoccurring injury has stunted his development the last few seasons.
As for the 49ers plans at wide receiver, Josh Morgan will likely become the No. 1 and he'll be joined by Ted Ginn on the opposite side of the field. The team has been rumored to be looking at various veteran free agent receivers, though.
Stay tuned to SB Nation Bay Area for complete updates on Michael Crabtree and his injured foot.