Practice Squad Eligibility Explained

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One aspect of the 53-man roster decisions that is often over-looked is the practice squad. If you have two guys that are neck-and-neck, and one can be signed to the practice squad, that player will almost always be the one cut. Practice squad eligibility is far more complicated than you would think. Here is the excerpt from the collective bargaining agreement explaining:
The Seahawks that appear to be practice squad eligible (based on a few different sources) are:
All drafted rookies
WR Kole Heckendorf (likely candidate)
TE Cameron Morrah 
OL Jeff Byers
OL Mitch Erickson
OL Gregg Peat
OL Jacob Phillips
DT Rob Rose
LB Joe Pawelek
S Kevin Ellison (I don’t understand how he’s eligible since he played 13 games, so question this one)
S Jamar Adams
CB Kennard Cox
CB Cord Parks
CB Marcus Brown
CB Josh Pinkard
There may be more. Note that LB Matt McCoy and Tijuan Hagler do not appear on the list.