PHILADELPHIA (973espn.com) - With LeGarrette Blount signing with Detroit during free agency, Jay Ajayi is expected to be the lead back in Philadelphia's running-back-by-committee approach this season with Glassboro native Corey Clement and veteran Darren Sproles mixing in from there.

BELL COW

“[Ajayi} came in last year and obviously proved to us that he can handle it,” coach Doug Pederson explained during minicamp. “He’s definitely going into camp as the No. 1 guy."

Pederson has stuck to a committee approach since he took over the team before the 2016 season and Ajayi will be the third name in three seasons expected to headline following Ryan Mathews and Blount, which highlights the volatility of the position.

Muddying things even further this season are the facts that Ajayi is entering a contract year and the one player Pederson trusts more than any other in the backfield, Sproles, will be back after tearing his ACL and breaking his forearm against the New York Giants in Week 3 of last season.

Ajayi, of course, was drafted by the Miami Dolphins in the fifth round of the 2015 draft and was traded to the Eagles at the deadline last season for a 2018 fourth-rounder. He developed into a Pro Bowl selection with the Dolphins after a 1,272-yard year in 2016 but was off to a poor start last season when Adam Gase pulled the plug in an effort to shake up his locker room.

Ajayi rebounded to average an impressive 5.8 yards-per-carry over seven games in Philadelphia and was a key cog in the RB-by-committee setup the Eagles used to reach a Super Bowl LII championship.

Pederson also lauded the Boise State product for the shape he arrived in during the spring, something related to Ajayi's off-the-field behavior. The London native hired a personal chef and also brought his own trainer with him to Philadelphia.

"He's been awesome," assistant head coach/running backs Duce Staley said when discussing Ajayi. "... He's one of those guys that has spent a lot of time in the film room. I still remember when we got him during the week (following the trade with the Miami Dolphins). He was eager to learn, he wanted to know more. It's like he was just plugged in with no problems, and he kept getting better each week."

On the final year of his rookie deal signed with Miami, Ajayi is set to make just under $2 million this season. Complicating matters on a potential extension are a number of issues, including a degenerative knee condition, the Eagles' salary cap problems as a whole, the team's belief in Clement, and the devaluation of the position league-wide.

THE COMMITTEE

Clement is a great story. The local kid who went undrafted and ended his rookie season as a Super Bowl hero. A hard-working, coachable player who swam with Staley's advice by losing weight and tirelessly trying to improve his blocking and receiving skills, Clement has gone from roster long shot to key contributor in a calendar year.

“Being with Duce every day has really helped,” Clement said. “He believes in me and I’m not going to let him down."

The 5-foot-6 Sproles is at another level when it comes to pass protection and catching the football out of the backfield but at 35 with 14 NFL seasons under his belt and coming off the ACL, he's best suited for a limited role in what will likely be his final pro season.

THE COMPETITION

The competition for the fourth spot figures to be intense with Matt Jones, a former starter in Washington who has had fumbling issues, trying to knock off former draft picks in Wendell Smallwood and Donnel Pumphrey.

“We have a lot of great guys," Pumphrey admitted. "I just want to control what I can control, work on my game and compete in training camp."

Pedigree saved Pumphrey last season in what is supposed to be a meritocracy. If you ignore what went on at San Diego State and the fact that Pumphrey was a fourth-round pick the Eagles traded up for last year, a disappointing preseason and the inability to handle the gruff nature of Staley had the rookie far behind his peers and falling.

Yet, Howie Roseman decided to ignore the-best-53 cliche and keep Pumphrey on the roster.

“We’re in a unique industry where there’s really no patience,” the Eagles executive explained at the time “We trust our evaluations and our scouts. And we want to give guys time that we believe in.”

Pumphrey was essentially redshirted, inactive on game day before being moved to injured reserve with a hamstring injury with the directive clear -- get tougher, both physically and mentally.

Listed at 5-foot-9 and 176 pounds, genetics have predisposed the reality that Pumphrey is never going to be Earl Campbell but there was plenty of room to get stronger so he went to the guy who he is ultimately tasked with replacing someday, Sproles.

As noted Sproles is just 5-foot-6 and 190 pounds but has lasted 14 years in the NFL and, pound-for-pound, is perhaps the strongest member of the Eagles with a powerful lower body that any RB should strive for.

As one former Eagles coach often told 973espn.com "Sproles is short, he's not small."

Pumphrey worked out with Sproles in San Diego during the offseason and claims he is up 10 pounds. The end game is far more than that, however. When the Eagles told Pumphrey to put on weight last season he did but it was not necessarily in the right places.

The 23-year-old who showed up for offseason work was more defined yet still had the signature quickness that was his calling card as the NCAA's all-time leading rusher at SDSU.

"It’s a different first day," Pumphrey admitted. "Last year, I didn’t really know what to expect. I didn’t know the playbook as much as do now, so it’s really just playing ball now and I’m able to move fast."

Maybe the bigger issue was repairing the relationship with his boss, however. With plenty of time for retrospection, Pumphrey had a heart-to-heart with his position coach in the hopes of putting pre-conceived notions from both sides in the rear-view mirror.

"I've matured a lot," Pumphrey said. "... I was taking a lot of criticism from [Staley] and I just felt like that’s where I needed to look at myself in the mirror and really just learn from him. It’s not about how they’re saying it; you just have to listen to the message they’re saying. That was the biggest thing, being coachable."

And who knows, maybe the "college Pump" as Roseman describes it ultimately shows up.

“There’s no other industry where you take a guy out of college and if they don’t look exactly like you’re hoping a month in, you just look to dump them,” Roseman said. “We want to develop our players.”

DEPTH CHART:

RB1 Jay Ajayi: Big bruising back motivated to produce during his walk year.
RB2 Corey Clement: Glassboro native is on track to be the Eagles' lead back by 2019.
Third-down back/RB3 Darren Sproles: Veteran wants to go out on his own terms.

ON THE BUBBLE:

RB4 Donnel Pumphrey: Undersized fourth-round disappointment from a year ago needs to prove he's strong enough for the NFL.
RB5 Matt Jones: If Jones can hold onto the football, he will likely make the team.
RB6 Wendell Smallwood: Staying on the field has been an issue for the Wilmington native.
RB7 Josh Adams: Stress fracture in his foot may limit the former Notre Dame star's ceiling to the practice squad right now.

POSITION GRADE: 6.0

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