Former Pro Bowl defensive lineman Sean Gilbert is embarking on a campaign to take over the NFL Players Association.

Gilbert—who as a player was known for his hardball negotiating tactics and large salary—has penned a 23,000-word e-book outlining his plan and announcing his candidacy for executive director of the union. That position is held by DeMaurice Smith, a Washington-based attorney who took over in 2009 for the late Gene Upshaw.

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