Without pads and contact, there is little evaluation that can be done of the offensive or defensive lineman outside of participation. It's pretty tough for a lineman to raise his stock against a blocking sled.
Organized team activities are more of an opportunity for the receivers, backs, linebackers and the secondary to show off their athleticism and natural ability.
There are numerous determining factors that indicate a player with a rising stock, but having the starting quarterback or head coach mention your name is usually a good place to start.
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Article Source: Bleacher Report - Oakland Raiders
