Entering his fourth season, Tryon started six games with the Indianapolis Colts last season, recording 44 tackles. He had seven tackles in the first three games this season before being waived.
To make room for Tryon, the Giants (3-1) released Williams on Wednesday. He played sparingly in four games, making one tackle.
The Giants also late Tuesday signed offensive lineman Jim Cordle from their practice squad, terminated the contract of wide receiver Brandon Stokley with an injury settlement and terminated the contract of quarterback Sage Rosenfels and removed him from injured reserve.