The Eagles enter Sunday's game against the Baltimore Ravens with uncertainty on the offensive line and depth concerns at running back - a bad combination for an offense that already had problems.

Offensive lineman Allen Barbre did not practice for the third consecutive day because of a hamstring injury, making it likely that rookie Isaac Seumalo will start at right tackle. Barbre is officially listed as questionable, but Seumalo took the first-team snaps all week. He would be the fourth starter and fifth player at that position this season. Seumalo was supposed to be an interior linemen, but injuries and suspension left the Eagles with no better option.

At running back, Darren Sproles has still not been cleared to return from a concussion suffered on a brutal hit he took while trying to field a punt last weekend. Wendell Smallwood is already out for the season, leaving the Eagles with Ryan Mathews and Kenjon Barner at running back and Byron Marshall promoted from the practice squad to be the third-stringer.

The Eagles have not scored more than two touchdowns in a game since Week 2, and they're now limited on the offensive line and in the running game against the NFL's fourth-ranked defense. That could put a strain on rookie quarterback Carson Wentz.

"As the play-caller, I have to make sure that I'm doing Isaac justice by helping him if I can and when I can," coach Doug Pederson said. "You are aware as a quarterback. Your rhythm and timing have to be just at the utmost high, just get the ball out of your hand."

When the Eagles drafted Seumalo in the third round, they liked his versatility. But even Pederson admitted they didn't view him as a tackle. A tackle is "on an island" more than a guard, Pederson said, and has more one-on-one blocks. They also face edge rushers. On Sunday, it will be Baltimore's five-time Pro Bowler, Elvis Dumervil. Pederson said Seumalo "is very capable of handling" the position and has had a good week of practice.

Seumalo said he has no choice but to be ready. He's been tested by the Eagles' pass rushers in practice, although that's different from what happens in a road venue on Sundays. Remember Halapoulivaati Vaitai's first start at right tackle against Washington?

"Sundays is all about taking what you do the other six days and playing unconsciously," Seumalo said. "Because the more you think, the slower you play. The less you think about actually doing stuff and the more you just know it, the faster you can go out and have fun. That's what I always try to do. Monday through Saturday is going to be hard. Sunday is going to be fun."

Seumalo started twice at right guard this season in emergency situations when Brandon Brooks had day-of-game illnesses, so Seumalo did not have the chance to prepare for those starts. If he starts Sunday, he will at least benefit from a full week of practice.

"Each position has its own nuances," Seumalo said. "So being able to practice that, repetition is the greatest teacher."

To avoid problems like the Eagles experienced in Vaitai's first start, it would help if they can establish a running game and not drop Wentz back so often. Wentz attempted 46.75 passes during the Eagles' four-game losing streak and was sacked 11 times.

Pederson said the plan was never to have such an imbalanced offense, but the game situations dictated the pass-happy attack. The offense will be challenged trying to run against Baltimore's top-ranked rush defense and without Smallwood and Sproles.

"You just don't have to necessarily line up and try to run at them," Pederson said. "We do some things with our [run-pass option] game. I even think that the three-step passing game - the quick passing game - can kind of offset your run game a little bit. It keeps your quarterback from being hit. But you're still going to have to line up and try to go toe-to-toe with a good defense."

Sproles has played 50 percent of the offensive snaps this season, and Smallwood played 18 percent. Mathews will remain the lead runner, but Barner and Marshall will need to help fill the void that Sproles leaves. Pederson said the Eagles won't limit their game plan because Sproles is absent. Barner, who was inactive last week, will also return punts in Sproles' place.

"It's not really trying to fill his shoes, but going out and being who I am," said Barner, who is averaging 5.1 yards per carry and has three receptions. "I'm not trying to be Sproles. I'm being me."

Wentz has endured changes in the lineup throughout the season, whether it was five different offensive line combinations or games without each of his top pass-catchers. He's also been sacked more than all but seven other NFL quarterbacks and attempted more passes than all but five. But he will continue to lead the team, with Pederson giving no consideration to sitting Wentz for the purpose of preservation.

"Not at all," Pederson said. "I'm a big believer in [finishing] this thing out the right way, and [playing] our guys. We play the guys that have been there all season long, and he's been a big part of that. . . . I don't want to send that type of message not only to him but to the team."

Extra points

Sproles and Vaitai (knee) are the only players who have been declared out for Sunday. Barbre is one of five players who are questionable. The others are tight end Brent Celek (stinger), wide receiver Dorial Green-Beckham (abdomen), linebacker Kamu Grugier-Hill (illness), and wide Jordan Matthews (ankle). Other than Barbre, they were all full participant in practices and appear on track to play. . . . Pederson said it's "almost a no-brainer" to put Lane Johnson back in the starting lineup when he returns from a suspension next week.