Thornton was a third-round draft pick by the Packers. The Patriots claimed him off waivers from Green Bay last month. He had already been released once and signed to the practice squad.
Williams was a third-round draft choice by the Houston Texans in 2013. He was released by Houston and went to training camp with Jacksonville this summer. His father, Brent Williams, played defensive end with the Patriots from 1986-93.
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