Jason Peters returns to Eagles to save Nick Foles | Marcus Hayes

JP makes everything better.

Peters returns Thursday night to protect Nick Foles' blind side, which, frankly, can be very blind. The other candidates to play left tackle are Halapoulivaati Vaitai, the only Eagle who had a worse preseason than Foles, and rookie Jordan Mailata, a converted rugby player with unlimited potential but zero football experience. The importance of Peters' return cannot be overstated. He is the cavalry, charging over yonder hill.

Some quarterbacks can function without the aid of an impenetrable offensive line. Foles is not among them.

They might pass quickly, like Eli Manning and Ben Roethlisberger. Last season, in his two full regular-season starts and his three playoff games, he held on to the ball an average of 2.78 seconds, or about as long as Larry King holds on to a wife. Two-point-eight seconds would have ranked Foles 34th if he'd thrown enough passes to qualify for the regular-season rankings. There are only 32 teams.

They might elude, like Russell Wilson and Carson Wentz, who is the quarterback Foles will replace until doctors agree that Wentz's reconstructed knee won't collapse. Foles couldn't elude a steamroller. In six seasons he has 351 rushing yards, and that includes his postseason total: 1.

His teammates don't bother to minimize Foles' shortcomings. Asked why Foles played so poorly in the preseason, the answer was consistent and simple.

"When we give Nick Foles time to get comfortable, sit back there and make throws, he plays better," said center Jason Kelce. "When he has an offensive line that can give him time to throw, he can be a dominant quarterback in this league."

When protected, Foles can be a Pro Bowl MVP, as he was after the 2013 season. When comfortable, Foles can be the Super Bowl MVP, as he was Feb. 4. Or, he can be the skittish bumbler who gave away two fumbles, two interceptions and a safety in two preseason starts.

So, when Peters returns, Foles will be comfortable?

"Ha! JP being out there would make anybody feel more comfortable," Kelce said.

At this moment there might more important players on the roster, considering the Eagles won the Super Bowl without Peters, who blew out his right knee in Game 7.

Begin with three-time Pro Bowl defensive tackle Fletcher Cox; continue to right tackle Lane Johnson, who might be the best tackle in the NFL; and, of course, Wentz, who, like Peters, watched the Birds win the Lombardi.

But the entire roster was built around Peters. He's been to nine Pro Bowls, four more than Cox, Johnson and Wentz combined. Last year, at 35 and in his 14th season, Peters was on his way to his 10th overall and his fifth in a row. He finished the year ranked third overall among tackles and second in pass blocking, according to Pro Football Focus.

"At this point," Kelce said, "he's a living legend."

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Peters' presence doesn't cure all ails, but his presence affects everything. Not even a "living legend" will keep receivers from dropping passes, but it should give them another heartbeat to get open. He won't help his defense sack the opposing quarterback, but he might keep the Eagles' offense on the field a few minutes longer, which means the defense will be fresher. Johnson distilled it nicely:

"Pretty much, if me and JP do our job, we usually come out with a win."

If that's true, then how did the Eagles go 11-1 in their 12 meaningful games after Peters' injury? They did it thanks to Vaitai … or, perhaps, despite Vaitai. PFF ranked Vaitai 48th out of the 51 tackles who took at least 750 snaps last season, even though he often had a tight end, guard or running back helping him block. With help, Vaitai played well enough. Peters needs no help.

"We put an emphasis on our tackles being able to block one-on-one because we want to keep it firm inside," Kelce noted. "Being able to get three-guys-thick inside means those tackles are going to be locked up against the best past rushers in the league. Jason Peters has been doing it longer and better than any tackle in the league."

Sound, independent tackle play simplifies everything. The Eagles constructed the team around this concept when they rode Tra Thomas and Jon Runyan to the Super Bowl after the 2004 season, and they have done so again. Since 2016, the Eagles committed almost $100 million to Johnson and Peters.

>> READ MORE: Will Fletcher Cox need to wreck the Falcons again?

When tackles operate on an island, it amplifies the potency of an offense, and even more so an offense like the Eagles', which emphasizes passes to running backs and tight ends. It also means that Pro Bowl tight end Zach Ertz and his protege, second-round rookie Dallas Goedert, become dangerous weapons. Foles uses his tight ends like Charlie Brown's pal Linus uses his blanket.

"If we protect the edges, it's going to allow Ertz to get open, and Dallas is on his way to being a great tight end, too," Johnson said. "It'll create a lot of mismatches with their height and versatility, especially in the red zone."

Peters' return doesn't guarantee perfection from an offense that failed to score in the preseason; just improvement. The return of receiver Nelson Agholor and running backs Jay Ajayi and Darren Sproles, all of whom missed time in the preseason, won't immediately make the Birds the best they can be; just better. They'll still be missing Wentz, as well as No. 1 receiver Alshon Jeffery, who team sources expect to miss at least the first two games as he recovers from shoulder surgery.

"Continuity and getting more reps with guys is always going to be beneficial," Kelce said. "Those little details that come with that make a big difference."

In the short term, though, Peters' return will make the biggest difference for the team's most inconsistent player: Nick Foles.

"It's a peace of mind" for Foles, Johnson said. "In your subconscious — he's been a pillar, such a dominant force — you have that in the back of your mind. That's your insurance."

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