The Giants waived/injured Horne (Achilles) on Sunday, Dan Salomone of the team's official site reports.
Horne suffered a torn Achilles' tendon in Saturday's preseason contest against the Jets. If he goes unclaimed, Horne will revert to the Giants' injured reserve list. Horne appeared in 21 games for the Falcons and Giants over the previous two seasons, recording 31 tackles (13 solo) and two pass deflections.