PHILADELPHIA (973espn.com) - First it was Allen Barbre and now Matt Tobin has been sent packing from the Philadelphia Eagles offensive line.

And it can all be traced back to the 2016 draft when Howie Roseman was able to secure Isaac Seumalo in the third-round, Halapoulivaati Vaitai two rounds after that, and finally former LSU tight end Dillon Gordon as an undrafted free agent.

Those are the names that are responsible for the two veterans being sent out west, the highly-regarded Barbre to Denver for a conditional 2019 seventh-round pick and Tobin to Seattle, along with a 2018 seventh-rounder, for a fifth-round selection next season.

In the case of Barbre, the Eagles probably would have liked to keep the 33-year-old around to be the game-day swing tackle behind Jason Peters and Lane Johnson but Barbre believes he should be a starter and after Philadelphia committed to Seumalo at left guard that had the former starter asking to be traded or released.

And when that domino fell, that put Tobin, who has started 21 games over his four seasons with the Eagles, back into the equation for depth purposes.

Once Seattle lost its starting left tackle George Fant to a torn ACL, however, desperation took over and the organization scoured the league for offensive line help. Roseman picked up the phone and was willing to part with Tobin because of the improvement of both Vaitai and Gordon.

Vaitai is set to be the swing tackle this season while Gordon is a versatile jack-of-all trades, part Peters backup, part extra tight end and even the fullback on occasion.

"I'm really comfortable," Pederson said when asked by 973espn.com about his perceived dwindling depth. "I say that because of what ‘V’ [Vaitai] did for us last year, stepping in when [T] Lane [Johnson] was not with us. Obviously, comfortable with [T] Jason Peters and [T] Lane [Johnson] as our starters and Big V [T Halapoulivaati Vaitai] as the swing tackle that can go left or right. And then after that, Dillon and [T] Taylor [Hart] are working and competing, and [T] Victor Salako is in that group.

"These next couple weeks will be important for these younger guys to see where they're at and really solidify a role on this team."

Vaitai started seven games when Johnson was serving a PED suspension during his rookie season and was slowed a bit during camp with a sprained MCL but is now back practicing at full speed.

Offensive line coach Jeff Stoutland has developed a plan to both keep the aging Peters on a pitch count while getting Vaitai all-important reps on the left side with the first team.

"If you notice when Jason is getting a breather, "V" will be in there with the ones at left tackle and then he will stay in there with he second-team at right tackle. It's extra reps for him but he's young, he can handle it," the OL coach  said.

Vaitai played at both left and right tackle in college at TCU but he was in a spread offense and rarely asked to do the kind of things he's now being told to do on the pro level. The main hurdle is footwork as the starters get to concentrate on one position while a backup like Vaitai has to be adept at several.

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen