FRISCO, Texas — Dallas Cowboys linebacker Sean Lee has been ruled out of Sunday's game against NFL-leading Philadelphia because of a hamstring injury.

The 2016 All-Pro was injured in the first quarter of last week's 27-7 loss to Atlanta. The Cowboys lost both games he missed because of hamstring issues earlier in the season and gave up three touchdown drives after the injury against the Falcons.

Justin Durant is expected to be active and could start at middle linebacker with the Cowboys moving Anthony Hitchens to Lee's weakside spot.

Jaylon Smith, a second-year player who missed his rookie season recovering from a college knee injury, saw increased time after a preseason knee injury that sidelined Hitchens the first four games and Lee's earlier hamstring issues. But the former Notre Dame standout has struggled with consistency.

Left tackle Tyron Smith is questionable with groin and back issues after missing the loss to the Falcons and sitting out of practice all week. His replacements allowed six of Atlanta's eight sacks.

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