PHILADELPHIA (973espn.com) - In a yet another blow at a position the Eagles can hardly afford it, backup middle linebacker Joe Walker will miss his rookie season with a torn ACL suffered in Thursday’s preseason game against Pittsburgh.

Although only a seventh-round pick Walker has been so impressive in the offseason work as well as in training camp he was virtually assured of making the final 53-man roster and both head coach Doug Pederson and defensive coordinator Jim Schwartz had singled him out on multiple occasions as a younger player who had stood out.

Les Bowen of the Philadelphia Daily News was the first to report than an MRI in Friday has confirmed what the Eagles feared after Walker heard a pop in his knee.

Meanwhile, cornerback Aaron Grymes, who had been making a strong push to make the final roster is likely out for the rest of the preseason with an AC joint injury in his shoulder.

Najee Goode, who has been working with the first-team at weakside linebacker in place of the injured Mychal Kendricks (hamstring) is the top reserve at every linebacker position for Schwartz while veteran Deontae Skinner and undrafted rookie free agents Quentin Gause and Myke Tavarres are top options in-house.

The Eagles have already been linked to veteran MLB Stephen Tulloch and that interest in bringing in someone from outside the organization may speed up with the injury to Walker.

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen

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