PHILADELPHIA (973espn.com) — Down two defensive tackles and up a safety for this weekend's game against the Los Angeles Chargers, the Eagles made an adjustment to the back end of the 53-man roster Saturday by promoting Justin Hamilton from the practice squad and waiving Trae Elston.

Pro Bowl defensive tackle Fletcher Cox was officially ruled out for Sunday's game against the 0-3 Los Angeles Chargers with a calf injury suffered during the first half of the Week 3 win over the New York Giants.

Cox has not been able to practice all week and one of his potential replacements, second-year DT Destiny Vaeao remains out with a wrist injury, meaning Beau Allen will likely start against the Chargers and rookie sixth-round pick Elijah Qualls was the only interior backup until Hamilton was promoted.

Both Brandon Graham and Vinny Curry could also end up getting reps inside next to Tim Jernigan in obvious passing situations with Chris Long and/or Derek Barnett filling in outside.

Hamilton, 24, spent the offseason with the Eagles and impressed during training camp at times. At 6-foot-2 and 315 pounds, he gives Jim Schwartz another big body to help contend with the Chargers' impressive Melvin Gordon-led running game.

Meanwhile, while defensive backs Corey Graham and Jaylen Watkins were ruled out Friday The good news is that the third of the "hamstrung trio," safety Rodney McLeod should be back, enabling Chris Maragos, who started against the Giants, to go back to his more familiar role on special teams.

Elston, who was picked up on waivers from Buffalo as emergency help at safety before the Giants game, is the odd man out.

-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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