LAST YEAR, for the first time in more than a half-century, one team produced both the NFL rushing champ and the league passing leader.
That, of course, was the Eagles. LeSean McCoy ran away with the rushing title with 1,607 yards, 268 more than runner-up Matt Forte, of the Chicago Bears.
Nick Foles had a league-best 119.2 passer rating, which was 4.1 points better than league MVP Peyton Manning.
The last team to produce both the league rushing and passing champs in the same year was the 1962 Green Bay Packers, who were coached by a fellow named Vince Lombardi and were in the middle of an era of dominance that saw them win five league titles in a 7-year period.
The common denominator in McCoy's and Foles' outstanding seasons was an incredibly athletic offensive line that featured two first-team All-Pros (left tackle Jason Peters and left guard Evan Mathis) and helped the Eagles set franchise records for total points and yards.
A year later, that same unit - minus second-year right tackle Lane Johnson for the first four games - is poised for yet another season of offensive dominance through the air and on the ground.
"I feel really good about the progress we've made and how we've played as a unit and how we will play as a unit," Mathis said.
"I see everything being better. It's not brand-new to us anymore. We have experience doing it. If there's anything any of us had flaws at, we've worked really hard at correcting those, as well as improving on every other aspect of the game."
In a testament to either good fortune, clean living or the wonders of sports science - or more probably, a combination of all of the above - the Eagles' five starting linemen didn't miss a game last season. Combined, they missed a total of 94 just 5,520 snaps.
That won't happen this season, if only because Johnson will sit out Games 1 through 4 after violating the league's policy on performance-enhancing drugs. He will be replaced by Allen Barbre, who will make just his eighth career start Sunday against Jacksonville.
"I'm comfortable with him," Mathis said. "I trust him to get the job done."
Barbre, who hasn't started a game since 2009, is considerably less athletic than former college quarterback and tight end Johnson, and has had to make the move from the left side of the line to the right. But he's had all summer to get ready.
"He's not getting thrown into the fire," Mathis said. "He didn't find out just last week that he's going to be starting at right tackle. He's been groomed for this. He's ready for this. And he knows what he has to do."
The Eagles are catching a bit of a break in a couple of those first four games without Johnson. Their Week 2 opponent, Indianapolis, will be without league sack king Robert Mathis, who also is serving a PED suspension.
And their Week 4 foe, San Francisco, will be without their best pass rusher, Aldon Smith, who was slapped with a nine-game suspension for violating the league's substance-abuse and personal-conduct policies.
"Barbre is just adequate," an NFC pro-personnel scout said. "He struggled in the preseason out there on the edge.
"The Eagles want to get five [receivers] out when they throw the ball. They don't want to chip or leave a tight end or back in because the offense isn't as aggressive and the spacing isn't the same.
"If Barbre has to face an elite guy, he's going to struggle. He struggles with spin moves and with guys getting underneath him. He's just OK out there. I'd have a lot fewer concerns about him if he was inside at guard and not out on an island against fast edge rushers."
There are no concerns about the rest of the offensive line, though. Peters, Mathis, right guard Todd Herremans and center Jason Kelce have combined for 332 career starts.
The soon-to-be-32 Herremans has a unit-high 116 starts. Peters, 32, has started 113 games and has been to six Pro Bowls. Mathis, also 32, has 69 career starts and one Pro Bowl invite.
Kelce, 26, who is expected to be the next Pro Bowler on the unit, has logged 34 starts. The only 14 games he hasn't started were the ones he missed in 2012 after tearing an ACL.
"Kelce is developing into one of the best centers in the game," the NFC scout said. "He's not the biggest guy in the world, so he can't overpower the big nose tackles. But I watched him play against New England last month and he just wheeled around Vince Wilfork the whole game. He shielded him easily.
"His hands are so good and he just runs so well. He gets to the second level. He can lead sweeps all the time. He can snap and get out. He's just extremely talented at what they ask him to do."
None of the three thirtysomething players on the line is showing any signs of age. Herremans struggled at times last season after coming back from a surgically repaired foot. But he's had a solid camp and preseason and says he feels better than he ever has in his career.
Mathis, who spent much of the early portion of his career as a journeyman backup, has developed into one of the league's top interior linemen since signing with the Eagles in 2011 as an afterthought free agent.
"He found the perfect system in Philadelphia when Howard Mudd was there [as the offensive-line coach under Andy Reid]," the scout said. "Howard gave him that chance, and then Chip Kelly came along with an offense that really caters to what he does best. A lot of one-on-one stuff. Peters on one side of him, Kelce on the other.
"He's not small [6-5, 298], but he's not like one of those giant guards. He's smart, conscientious. It's not easy to play offensive line in that system because, with that tempo offense, you have to process information in like 2, 3 seconds. But he's good at it. They're all good at it."
No one's better than Peters, whom Mudd has compared favorably to another guy he coached: Walter Jones, who this summer was inducted into the Pro Football Hall of Fame in his first year of eligibility.
"Peters is what, 32? But he's in his prime," the scout said. "He's the best left tackle in the game, hands down. I'd like to see him hold. He doesn't hold at all. He just punches people. If he ever did what Walter Jones used to do and just locked people up with his hands and pulled them to his body, they wouldn't be able to move."
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