SEATTLE - The Eagles played without their top two running backs in the second half of their 26-15 loss to the Seattle Seahawks. When they return to Philadelphia, they'll have a better idea of how much longer they'll be without Ryan Mathews and Darren Sproles.

Mathews exited the game with a knee injury and Sproles with a rib injury. "I'll find out more when we get back," coach Doug Pederson said after the game.

Mathews rushed seven times for 31 yards before his injury. Sproles had two carries for 15 yards and one catch for 6 yards. Wendell Smallwood and Kenjon Barner replaced them. Smallwood was the leading rusher with 13 carries for 48 yards. Barner had three carries for 17 yards.

"It was tough," quarterback Carson Wentz said. "With Sproles, he creates mismatches in the passing game. Ryan Matthews, obviously he's been running great for the last few weeks. He started off today really strong. But Wendell and Kenjon, we have a lot of confidence. I think that's one position we have a lot of depth at, so I think those guys stepped up big."

Vaitai hurt, too

Halapoulivaati Vaitai exited the game late in the fourth quarter with an apparent knee injury. Pederson did not have word on his injury after the game.

For the first time this season, the Eagles did not activate backup tackle Matt Tobin and used two interior linemen as the reserves. That decision was tested when Jason Peters left the game in the first half with a forearm injury. He returned to the game after getting X-rayed.

Stefen Wisniewski entered at left guard and Allen Barbre slid over to left tackle.

"Nine times out of 10 I'm working, I know what the tackle is doing, I am playing right next to him," Barbre said. "I don't want to be up there calling protections, but I dang near could tell you what the tackle has if I know what I am doing."

McKelvin exits

Cornerback Leodis McKelvin left the game in the second half to be tested for a concussion. The Eagles rotated their cornerbacks before that point, using McKelvin, Nolan Carroll, and Jalen Mills in the two outside spots.

Defensive linemen Fletcher Cox and Connor Barwin left the field with injuries in the second half, but both players returned.

Ertz, Matthews play

Eagles wide receiver Jordan Matthews and tight end Zach Ertz were both in the lineup even though they were listed as questionable on the final injury report. Matthews had back spasms leading up to the game and Ertz injured a hamstring in practice on Wednesday.

The Eagles' inactive players were safety Terrence Brooks (hamstring), cornerback Aaron Grymes, defensive end Steven Means, defensive tackle Taylor Hart, and offensive linemen Josh Andrews, Dillon Gordon, and Tobin.

Barbre was back on the field after missing two weeks with a hamstring injury. Linebacker Kamu Grugier-Hill returned to action after a three-week absence because of an injured hamstring.