Ryan Mathews experienced stiffness in his left ankle early in the Eagles' 34-3 win over the Pittsburgh Steelers, an injury that limited Mathews to only eight snaps in the game. Coach Doug Pederson said Monday that Mathews would remain the team's top running back as long as he's healthy.

Mathews was bothered by the same ankle that hindered him before training camp. He injured the ankle in the season-opening win over Cleveland when another player rolled on it. Mathews was not on the injury report and was a full participant in practice, but his heavily taped ankle was apparent. The Eagles gave him two early carries Sunday before eventually taking him out of the game.

"It never loosened up and kept getting stiff," Pederson said. "Just opted on the side of caution more than anything else."

The offense relied on Darren Sproles, Wendell Smallwood, and Kenjon Barner at running back. Smallwood played 23 snaps, Sproles 24, and Barner 12.

That group impressed in Mathews' absence. Smallwood rushed 17 times for 79 yards and a touchdown. Barner had eight carries for 42 yards and a touchdown. Sproles had six catches for 128 yards and a receiving TD.

"When Ryan is healthy, he's the guy," Pederson said. "We mix Darren in there. You saw what Wendell can do. … Kenjon, we know what he's all about. Everybody is a little different runner."

Pederson said Smallwood is best inside the tackles, and Barner helps outside the tackles. Sproles is a weapon in the receiving game.

Mathews, who topped 1,000 rushing yards in the two seasons when he has played at least 14 games, is averaging 3.2 yards on 33 carries this season. He had 22 carries in the season opener, and Pederson said that's how the Eagles want to use him.

"I think that's a good number for him, honestly," Pederson said. "Then if everybody else can get a few touches after that, I think you are on track."

Ertz is expected to return

The bye week arrives at a good time for the injured players on the Eagles. Tight end Zach Ertz is expected to return from a displaced rib when the Eagles start practicing for the Detroit Lions next week. Ertz missed two games.

Leodis McKelvin, who has also missed two games with a hamstring injury, is expected back next week, too.

Offensive lineman Isaac Seumalo has dealt with a pectoral injury since the preseason and missed practice last week. He has been inactive for the first three games of the season and is expected to practice next week. Seumalo could be active if Lane Johnson's suspension begins in Week 5.