Jay Ajayi will arrive at the stadium Saturday for the Eagles' playoff game, but it won't be Ajayi running for the Eagles. To hear Ajayi tell it, it will be the "Jay Train" on the field.

Ajayi grabbed the gold, locomotive-shaped medallion from under his shirt and rubbed it between his fingers when explaining the difference between the person and the persona. He started wearing it around his neck four years ago, soon after he adopted the "Jay Train" nickname. For the Eagles running back, "Jay Train" is more than a moniker. It's a mentality.

As a redshirt sophomore at Boise State in 2013, Ajayi wanted an alter-ego on the field – "that persona to take my game to the next level." A fan Photoshopped a picture of Ajayi on a train, and the character was on track.

"I thought it was kind of clever," Ajayi said.

Ajayi was jealous of a teammate's sack dance that would energize the crowd. He figured he scored enough touchdowns — he needed his own way to celebrate. So he started motioning as if he's pulling a train whistle as the conductor of a train. He did it at Boise State, brought it to the Miami Dolphins, and continued it in Philadelphia after the Oct. 31 trade to the Eagles.

"When I'm on the field, I can turn into the Jay Train, become kind of violent, physical," said Ajayi, who is 6-foot and 223 pounds. "It's almost like you can be violent on the field and it's legal a little bit because it's football. That's kind of where I can go with that persona and use it to be physical, to be a dog on the field. Use all those emotions to run and make plays for the team."

Eagles coach Doug Pederson has been honest about the team's need to run the ball in the postseason. He thinks it's part of the winning formula combined with a strong defense – implicit in that formula is that Nick Foles is starting in place of Carson Wentz – and it might be the best way to attack the Falcons. When the Eagles upset Atlanta last season, they rushed for 208 yards. And that was without Ajayi, whose 130 rushing yards on Oct. 15 while playing for the Dolphins are the most the Falcons have allowed all season.

Add those factors together, and it's not hard to realize a big part of the Eagles' game plan: Ride the Jay Train.

"The Jay Train is always out every week," Ajayi said. "As many seats [as possible]. First class, everything."

Outplaying a stellar quartet

The Falcons have faced four of the six Pro Bowl running backs this season: Todd Gurley, Alvin Kamara, Mark Ingram, and LeSean McCoy. Ajayi performed better against the Falcons than all of them.

"He's got excellent change of direction, so we lost some leverage on some tackles where he was able to extend some plays," Falcons coach Dan Quinn said.

Ajayi didn't have a run longer than 18 yards and only four rushes longer than 10 yards, but he didn't slow down; two of his 18-yard rushes came in the fourth quarter. Ajayi and Pederson watched film of the game this week. Although it's a different scheme, there's benefit in seeing Ajayi against a swarming Falcons defense that has kept opponents to 104.1 rushing yards per game this season.

"It's helpful from the standpoint of the success that he had and to be able to look at the types of runs that he had that game," Pederson said. "It's different circumstances and all that, but there wasn't a lot of like different concepts that they ran that we're doing now, type thing. A lot of it was similar."

The Falcons know Ajayi will likely be a big part of the Eagles' game plan and could put an extra defender closer to the line to force Foles to try to pass on them. Ajayi said a running back can still be effective against a loaded box, noting that if he can make it past the main wave of defenders, there's more room to navigate.

The best lesson for the Eagles from that Dolphins-Falcons game might have been Ajayi's volume. Ajayi had 15 second-half rushes against the Falcons – he hasn't had more than 15 rushes in a game since arriving in Philadelphia.

The Eagles prefer spreading carries among a few running backs. In Pederson's 32 games as a head coach, there have been only two games in which a running back had at least 20 carries – and both came last season. Ajayi had nine in an 18-game span with the Dolphins. The Eagles gradually increased his playing time, but they never committed to Ajayi as a workhorse running back. Pederson wasn't inclined to disrupt what he believed was working, and the Eagles had the third-ranked rushing offense this season.

But there's little question that Ajayi is the Eagles' most explosive running back. His 5.8 yards per carry since the trade rank second in the NFL during that span, and he had two of the team's three longest rushes even though he played only seven games. The Eagles might be more inclined to feature Ajayi in an elimination game. Offensive coordinator Frank Reich has called the carry distribution a "fluid thing," and the Eagles have taken strides to ensure Ajayi is fresh for Saturday.

Ajayi was the only offensive contributor to sit out the Week 17 game against the Cowboys. He missed one practice last week so he could rest his knee. Considering he hasn't played a game the past two weeks and had bye weeks during the regular season with both the Dolphins and Eagles, Ajayi benefited from more rest than a running back typically has at this time of the year. Ajayi has noted how fresh he feels, even if he didn't necessarily request the time off or reduced workload.

"I really do feel like he's fresh," Reich said, "and that is one of the advantages of what we've done and really managing that situation for him in whatever things he has going on physically."

‘Weapon X’

Ajayi saw videos of Brian Dawkins online this week. He can relate.

Dawkins is now a football operations executive for the Eagles, and when Ajayi sees Dawkins around the NovaCare Complex, he knows the Eagles icon as a calm, collected person who invites conversation. What Ajayi sees on Dawkins videos is not what he encounters in the hallway.

"You kind of see that 'Weapon X' alter-ego in those videos," Ajayi said. "That guy, he'll take anyone's head off. It doesn't matter who it is. That's Weapon X in those videos."

Ajayi undergoes a similar transformation when he turns from the laid-back London native who often has a beanie over his blond-dyed dreadlocks into an off-the-rails train.

"Some guys, you kind of get in your zone where everything is instinct and you're out there, emotions, you're just playing football," Ajayi said. "For me, it's being the Jay Train. I use that, and it's been great for me. I just go into an ultra-competitive mode, where it's like I'll get mad at my own mom if she was out there."

When describing his running style, Ajayi uses words such as "attacking" and "punish." A former striker in soccer, Ajayi could be a graceful runner. He wants to be an aggressive one. Running back Corey Clement called it a "refusal to be denied."

"Jay Train can stand for so much," Clement said. "He plays with so much hunger. He doesn't fear anything. When he's Jay Train, his fear level doesn't exist. …Some guys might have a tendency to second-guess themselves. But when Jay goes out there, Jay's 100 percent 'Jay Train.' "

Ajayi has already seen Eagles fans use his celebration in the stands. The Dolphins played a train horn when Ajayi ran out of the tunnel. He has played only three home games in Philadelphia, but it's something he'd like added when he takes the field.

"Hopefully one day when I get that opportunity, we can hear the train horn pretty loud when I come out," Ajayi said. "That would be pretty dope."

Saturday could be the start. If the Eagles commit to riding the Jay Train, they might be able to sound that horn a week from Sunday, too.

"It's been a long season," Ajayi said, "but I'm only hoping it's longer than this."