Emil Igwenagu was neck-and-neck with Michael Burton all preseason. Igwenagu's release indicates that the Lions liked the prospect of Burton's future better. Igwenagu spent most of 2014 on the Lions' practice squad, but unfortunately he is no longer eligible this year.
In addition to Igwenagu's release, Corey Wootton was sent to the IR list after suffering a torn pectoral muscle in the final preseason game, Josh Katzenstein reports.
The Lions have six more moves that remain unannounced, despite the fact that the 4 p.m. ET deadline has passed.
UPDATE: According to Dave Birkett, Joe Madsen was also released earlier in the day. That means the Lions only have five more moves to announce.