Nick Foles, DeMeco Ryans injured

HOUSTON -- The Philadelphia Eagles gained possession of first place in the NFC East while losing their signal callers on both sides of the ball.

Eagles quarterback Nick Foles and inside linebacker DeMeco Ryans were knocked out of Sunday's 31-21 victory over the Houston Texans at NRG Stadium.

Foles injured his left shoulder on the last play of the first quarter, when he was sacked by Texans linebacker Whitney Mercilus. The Eagles did not announce the exact injury or the amount of time Foles is expected to miss.

Mark Sanchez, who played three quarters in Sunday in his first regular-season appearance since 2012, will fill in until Foles, who was unavailable after the game, is healthy.

Ryans tore his Achilles tendon while making a fourth-quarter interception and is likely to miss the rest of the season, sources told ESPN. The 30-year-old Ryans left the Eagles' locker room on crutches without speaking to reporters.

"DeMeco is the true leader on our defensive side of the ball," Eagles head coach Chip Kelly said. "You know what DeMeco means to this team -- he's our true leader. He's Mufasa. He's our guy. But when a warrior goes down, you pick up his shield and play in honor of him. That's what our guys did."

The entire Eagles team walked onto the field to see Ryans off as he departed on a cart. He was cheered by Texans fans, who rooted for him for the first six years of his NFL career. Ryans was traded from the Texans to the Eagles in 2012.

As he went down with the injury, Ryans lost possession of the ball. It was recovered by Houston, which scored a touchdown two plays later.

Foles had highs and lows before departing. He threw a perfect pass to Jeremy Maclin for a 59-yard touchdown, but a few minutes later, his pass for Riley Cooper was intercepted and returned 51 yards for a touchdown by Texans cornerback A.J. Bouye.

As the quarter ended, Foles was sacked by Mercilus at midfield. He was slow to get up and walked off the field with a trainer before heading to the locker room for X-rays on his shoulder and collarbone.

Foles did not return to the contest, opening the door for Sanchez, who completed 15 of 22 passes for 202 yards, two touchdowns and two interceptions.

"I thought Mark did a really good job," Kelly said. "The one interception -- I think it hit wide receiver Josh Huff in the hands and was tipped. The other one, I think (Cooper) got spun around. Besides that, I thought he had a really good command of what we're doing.

"Since Day 1 here, you know what type of professional (Sanchez) is. ... We were fortunate when Nick did go down, we were able to bring Mark in. I don't think we missed a beat."

Eagles left guard Todd Herremans, who played in spite of a torn left biceps, left the game in the second half after injuring his ankle.