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Prisco's Preseason Week 1 observations
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The NFL has decided to play hard ball with James Harrison, Clay Matthews, Julius Peppers and Mike Neal.
In a letter that was written to the NFLPA on Monday, and obtained by CBSSports.com, the league announced that each player will be suspended if they don't cooperate with the NFL's investigation into allegations that all four players received performance-enhancing drugs (PED) from the Guyer Institute in Indiana.
The allegations were made in December in a report that was released by Al Jazeeera America.