Eagles place rookie LB Jordan Hicks (pectoral) on IR

The Philadelphia Eagles' linebacking corps suffered another blow, this one season-altering.

An MRI on Monday revealed that rookie Jordan Hicks tore his pectoral muscle in Sunday's victory over the Dallas Cowboys, NFL Media Insider Ian Rapoport reports, per a source close to the player. The injury was initially thought to be a pull, but tests showed worse news.

FOX Sports' Jay Glazer first reported the tear.

The Eagles announced Hicks was placed on injured reserve, ending his season. In a corresponding move, Philadelphia re-signed linebacker Emmanuel Acho.

Hicks was the Eagles' second-leading tackler after Week 9 and their biggest playmaker among inside linebackers. The rookie had compiled 50 tackles, one sack, three passes defensed, one forced fumble and two interceptions on the season. Watching Eagles film, Hicks was one of the few second-level defenders who made "wow" plays on a consistent basis each and every week.

Hicks was a menace to the rival Cowboys this season. His tackle of Tony Romo in Week 2 sent the quarterback to injured reserve for eight weeks. On Sunday, the rookie had a pick-six that changed the tenor of the contest.

Kiko Alonso returned from a knee injury Sunday, which should help mitigate some of the loss of the dynamic rookie. Hicks ranked eighth on Chris Wesseling's most recent Rookie of the Year watch.