If there is a problem at guard or tackle, the question gets more complicated.
"Well, it's simple math," Shurmur said, before mentioning Matt Tobin, a 2013 undrafted rookie who got into one game, Andrew Gardner, an offseason signing who has played in eight games over the past four seasons with Miami and Houston, and Dennis Kelly, the 2012 fifth-rounder who started 10 games that injury-ravaged season but did not appear in a game last year.
"That's just the reality of it," Shurmur said, after mentioning "a host of guys," almost all of whom are undrafted rookies, behind the top three. The Eagles did not draft an offensive lineman this year.
It's not hard to envision general manager Howie Roseman taking an especially long look at veteran o-linemen when teams start cutting down at the end of the month.
Other highlights from Shurmur's media session:
* The Jordan Matthews train keeps rolling. "He can play anywhere," Shurmur said. "He's got size. He's good against bump-and-run coverage. His spatial awareness is good."
The 6-3, 212-pound second-rounder can play inside or outside. But the tentative plan right now is for him to open the season as the slot receiver.
"There are different combinations of things that can happen when you're inside as opposed to outside," Shurmur said. "He kind of has a good feel for that. You've been able to see in camp that he's been able to get open and make plays.
"The other advantage is he's young and he's got courage. So he can run around and catch the ball with people around him. Lastly, when he catches the ball, he sets his hair on fire and runs. If we didn't have fences around here, he'd run into the street. He's one of the best finishers we have."
* Shurmur on Darren Sproles: "He can be a first down, second down, third down, fourth down, special-teams weapon. He's a weapon whenever he's on the field. You can see we're handing him the ball. We're throwing him the ball. We'll try to use him every which way we can. The nice thing about Darren - and this is the value added to him - he's had a great career. He's a highly productive guy. But he does everything absolutely right. He grinds on what he's doing and he finishes every play. Jordan as a young guy and Darren as a veteran, those guys are finishers."
* Shurmur on third-round rookie wide receiver Josh Huff: "He's done a good job. We're working him inside and outside. He walked in here thinking, 'Hey, I know this offense.' And he'll be the first one to tell you there's a lot of things that have changed and been added since he was at Oregon. Which we had to do. We see a lot more man-coverage in the NFL than they did in college. So we have a lot of the traditional things in the passing game that you would run at this level. That kind of shocked him initially, that this isn't exactly what we did at Oregon. But he's settled in and is doing extremely well. He's very good against bump-and-run. He's a strong, physical body. Almost looks like a running back because he's a powerful type guy."
* Safety Keelan Johnson, excused from the start of camp as he dealt with the aftermath of his arrest in Arizona for shoving a police officer, took the field for the first time yesterday, having missed 4 days of sessions. Johnson expressed his appreciation for Eagles coach Chip Kelly not cutting him over the arrest. He said he will need more time off in the coming weeks as the court case continues. He declined to discuss the incident.
* Corner Nolan Carroll broke a kickoff return and again was active defending passes.
* David Molk (6-1, 290) wrestled down grizzly-sized nose tackle Beau Allen (6-2, 333) in a blocking drill.
* Damaris Johnson, a longshot to stick around who needed a highlight catch, made one in the corner of the end zone, leaping to haul in a Matt Barkley pass.
* Brandon Graham was left flatfooted by a Nick Foles back shoulder throw to Brent Celek in the end zone. Graham was impressive in pass-rush drills, but the Eagles probably still don't want him covering much.
On Twitter: @LesBowen, @Pdomo