PHILADELPHIA -- When the Philadelphia Eagles open the NFL regular season against the Cleveland Browns on Sept. 11, someone will be lined up at right tackle.

That much, we're sure about.

If it is Lane Johnson, the 2013 first-round pick who has held the position for three years, then the Eagles can focus on other problems. There are plenty when you have a first-time head coach and a limited amount of offensive firepower.

If Johnson is suspended for 10 games by the NFL, then right tackle vaults to the top of Doug Pederson's list of concerns. That problem would be complicated if left tackle Jason Peters is not healthy enough to start and finish the game.

If Lane Johnson, left, is suspended for the first 10 games, the Eagles will be forced to shuffle their offensive line. AP Photo/Chris Szagola

For now, Matt Tobin will start at left tackle in the Eagles' preseason opener Thursday night against Tampa Bay. Tobin's 20 career starts have all been at guard, but Pederson has been impressed with his work during training camp.

"Matt Tobin is doing a good job at left tackle," Pederson said, explaining why he didn't plan to move Johnson over to that spot now. That might be the Eagles' long-term plan for replacing the 34-year-old Peters, but for now, Tobin can get them through a game or two. This way, Johnson can prepare to play alongside guard Brandon Brooks on the right side.

If Pederson has to replace Johnson on the fly, here are his options:

Matt Tobin. Signed as an undrafted rookie in 2013 -- the same year Johnson was the fourth pick in the draft -- Tobin has played in 30 games for the Eagles. He has started five games at left guard and 15 games at right guard. Thirteen of his starts came last year, after the departures of Evan Mathis and Todd Herremans. It is only fair to point out that Tobin's play was one of the reasons the Eagles spent $40 million to sign Brooks away from the Houston Texans.

Tobin might be a more natural fit at tackle, but he still hasn't protected a quarterback from the speedy edge rushers that tackles face weekly.

Dennis Kelly. The 6-foot-8, 320-pound Kelly was the Eagles' fifth-round draft pick in 2012. As a rookie, he was pressed into service when Herremans moved from right tackle to left tackle after Peters was injured. Kelly started 10 games for an Eagles team that went 4-12.

The amazing thing is that Kelly is still on the team. After his rookie year, Chip Kelly came in as head coach and changed everything about the way the Eagles do business. Dennis Kelly didn't play at all in 2013. He started three games in 2014. Last year, with a lack of continuity plaguing the offensive line, Kelly started two games and played in 12 others.

Andrew Gardner. When Johnson was suspended for four games in 2014, Gardner started two games at right tackle. He has also started games at right guard. The 6-6, 310-pound Gardner actually won the starting right guard spot last year coming out of training camp.

He started the first three games, then injured his foot. The Lisfranc sprain required surgery and Gardner spent the rest of the season on injured reserve. He is a quietly effective player when healthy, and could get the call if Johnson is suspended.

Allen Barbre. Barbre started seven games at right tackle for the Green Bay Packers in 2009. He would likely be the easiest solution for the Eagles if they had to replace Johnson.

At the moment, Barbre is the team's starting left guard. So moving him to tackle would mean a domino falling and leading to another problem. The Eagles could slide Stefen Wisniewski into the left guard slot and move Barbre to tackle, but that's something they should probably do sooner rather than later.

Barbre started 16 games at left guard last year. The Eagles' need for upgrades at the guard position was illustrated by the signing of Brooks. It was surprising that Barbre remained with the first team all through organized team activities and well into training camp. But there he is, and it might be more trouble to move him than to maintain continuity and find another solution at tackle.

Dillon Gordon. Former Eagles wide receiver Mike Quick was talking Gordon up at practice last week. Gordon played tight end at LSU and signed with the Eagles as an undrafted rookie. That is how Peters came into the league, as an undrafted tight end. So who knows? But it is hard to believe Gordon would be ready to step into the starting lineup after just a few months of practice.

Halapoulivaati Vaitai. The fifth-round pick should get a look, but that is a pretty big jump to ask a rookie to make.