When the Jaguars made the decision to place RB Rashad Jennings on the injured reserve list, they did so without disclosing the nature of his knee injury. Rotoworld noted that it was odd that an injury that didn't require surgery would be severe enough to end his season prior to his season ever beginning at all.
Weird. An ACL tear or patellar tendon tear would require surgery, and a minor meniscus issue wouldn't sideline Jennings for the year. It's possible Jennings just had a serious sprain of the MCL or PCL and the Jags didn't feel comfortable holding a roster spot for him.
Today, Rashad Jennings tweeted that he is one week away from being cleared by doctors.
It's hard to justify finishing Jennings's season by putting him on the injured reserve when it looks like he would've been available to play by week seven. Because he participated in training camp he was ineligible to be placed on the physically unable to perform list (PUP list).
The only rationale for the Jaguars decision is that they knew he would miss a significant amount of time and decided to get more value out of one of their 53 roster spots by using it on someone else. However, 10 games from Jennings would've been very valuable to the Jaguars season in 2011.