PHILADELPHIA (973espn.com) - For the Eagles to advance to the NFC Championship Game, the path forward could be the second identity of running back Jay Ajayi.

The "Jay Train" is set to board at Lincoln Financial Field on Saturday afternoon with a destination to be determined.

The 6-foot, 225-pound Ajayi came up with the "Jay Train" celebration during his sophomore season at Boise State and it's stuck as he's developed into an explosive professional with a pair of 200-yard rushing days and a Pro Bowl selection.

“I had seen a picture that someone had photoshopped me on a train or something like that," Ayayi explained. "I thought it was kind of clever. I just stuck with the Jay Train celebration when I scored and it just kind of became my persona on the field where I’m kind of a nice guy off the field, real chill. But when I’m on the field, I can turn into the Jay Train and become kind of violent, physical."

So much of the hype leading up to the divisional-round playoff matchup between the Eagles and the Atlanta Falcons has surrounded Nick Foles and whether or not the backup turned starter can reverse his late-season slump and at least give Philadelphia competent play at the quarterback position.

Foles' presence in the lineup instead of second-team All-Pro Carson Wentz is the reason the Eagles have tumbled from prohibitive favorite to the first No. 1 seed in the current playoff format to be an underdog.

“It’s not insulting,” Ajayi said when discussing the people who don't believe in his team. “That’s the storyline right now, that without ‘11’ [Wentz] we’re nothing. That’s what we’ve been hearing, and we’re excited to come out on Saturday and showcase what we can do.”

Instead of continuing to pound the square peg in the round hole, it seems as if Doug Pederson and Frank Reich are preparing to hitch the Eagles' fortunes to the train that ran over Atlanta's defense in a violent and physical fashion to the tune of 130 yards earlier this season when Ajayi still called Miami home.

To date, no Eagles runner has carried more than 16 times this season [LeGarrette Blount against the Chargers] but there are signs that's about to change.

Ajayi has been effective in Philadelphia, running for 408 yards on just 70 carries, an impressive 5.8 yards per rush but the Eagles have been slow to tinker with a RB-by-committee setup that has worked. The Eagles, however, rested Ajayi in Week 17 and even gave him a maintenance day during the bye week to help him deal with the chronic knee pain that has followed the dynamic back since his college days.

“It’s been ups and downs,” Ajayi admitted.

This season Ajayi has had plenty of rest first due to Hurricane Irma delaying the start of the Dolphins' season all the way up to his Week 17 vacation tied to the Eagles having already clinched the No. 1 seed in the NFC.

“I guess I got lucky in a way,” admitted Ajayi, who also got bye weeks in both Miami and Philadelphia due to the timing of the Halloween trade that sent him north. “I feel good right now. I’m excited for this challenge. It’s a one-game season.”

And that one game comes against a team Ajayi dominated back in Week 6 despite the Falcons committed to stopping him, a performance that set off a gleam in the eye of a player who hasn't exactly been media friendly.

“You’ve got to have a plan prepared for that extra defender,” Ajayi said when asked about his success against the Falcons. “At the same time, it’s almost like if you can get through that wave of the eight-man box, there’s a lot of space. When we make our plays and get through that, there will be big plays for us. ... I’ll be ready this Saturday.”

Ready to let everyone aboard the "Jay Train" for two more stops, the NFC title game and Super Bowl LII in Minneapolis.

“First class, everything, we’ve got it all,” Ayaji joked of the accommodations on the train. "...  I’m excited. I’m already further [in the playoffs] than I’ve been in my career. A No. 1 seed team with the opportunity to get a Super Bowl."

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen