This is a cultural phenomenon that dates back 20 years and the planning begins when the schedule is released and culminates when the Eagles take the field on foreign soil, buoyed by thousands and thousands of fans who have invaded the opponent's stadium.
"It's a takeover," said defensive end Brandon Graham, who has been part of the scene since the 2010 season. "It's amazing. It feels like a home game."
That's the idea.
Fan travel groups organize the trips, are joined by others who come from around the country – in some cases, from around the world, and are buffeted by Eagles fans who live in that particular city. Add it all up and the picture at kickoff on gameday or game night is something rather extraordinary: Eagles colors and "E-A-G-L-E-S, EAGLES!" chants rattle the corridors and the flood the playing field and, it has happened more than once, force a home-team quarterback and offense to work the silent count.
For home games.
The plans are starting now in households across the region. Fans are leaving on Thursday, or on Friday, and they're going to make a weekend of it in Los Angeles. And when they aren't visiting Rodeo Drive (can you imagine the ruckus about to ensue there?!) or Hollywood hot spots, they will party it up with fellow Eagles fans at night-before tailgate parties on Saturday to warm up for Sunday afternoon's main event: The Eagles at the Rams, a game with so much at stake with Philadelphia looking to extend its perfect start and Los Angeles (2-2) trying to keep pace in a competitive NFC West.
It's going to be fun and wild and, yes, Eagles fans are going to turn Los Angeles Eagles Green for a long weekend.
All of this makes a difference when the game is played. When the Eagles played in Tampa, Raymond James Stadium was awash in Eagles fans and Head Coach Nick Sirianni was so appreciative that he tried to go into the stands to slap hands and give hugs and thank the fans. Game after game, season after season, fans follow the Eagles by the thousands and bring their "A" game.
On Sunday, if you aren't there and you're watching on television or listening on the radio or the app, you will notice all of the Eagles noise. It's going to jump out at you.
"I mean, what an advantage. We have the best fans in the NFL. When you're playing a game in the NFL where the parity is so tight, that makes a huge difference. Everything makes a huge difference, especially the crowd noise. Especially the deflating of the opposing team when you come out and they're getting booed going through starting lineups," said Sirianni the day after the Eagles beat Tampa Bay, 25-11, and he was asked about the Eagles fans in the stands. "Trust me, I heard that, of what was going on there, and so that's a huge advantage. It's not a good feeling when you're on the other side. Obviously, I wanted to tell them how much I appreciated them. I wish I – I tried to go – I mean, I climbed up the stairs to go into the stands and the gate was there so I couldn't go up in there.
"I would love to have high-fived every one of them because they made a big difference in that game just right from the beginning."
And, one more thing from the head coach, just as a reminder, because it is obvious how much he and the team appreciate the fans' affection.
"We love our fans," he said.
Los Angeles, be prepared. Eagles fans are on the way.