The move should help the Dolphins get Andrew Van Ginkel on the field for more defensive snaps. Van Ginkel played 480 defensive snaps (46 percent) and a team-leading 324 special teams snaps (72 percent).
The Eagles acquired Riley in a trade with the Falcons during the 2019 season. Riley earned the “C” on his jersey for the 2019 postseason despite his late arrival.
He kept the captaincy in 2020.
Riley totaled 55 tackles, an interception and a forced fumble in 25 games in Philadelphia.
Riley also plays linebacker, seeing action on 569 defensive snaps and 255 on special teams last season. He started eight games in 2020.
The Eagles will have to address depth at the position with the departure of Riley and the free agent status of Nathan Gerry.