Just look at the numbers.
Through 13 games with the Eagles this season, Murray has rushed for a mere 606 yards and four touchdowns. Last year with the Dallas Cowboys, Murray led the league in both rushing yards (1,845) and rushing touchdowns (13). He's currently on track to finish with 699 yards -- making him about a third as productive as he was in 2014.
The problem lies in his fit with Philadelphia's offensive scheme, and as a result, his role is smaller than it was in Dallas.
Chip Kelly's high-powered spread offense revolves around spacing. The majority of snaps take place out of the shotgun formation, with the goal of capitalizing on the gaps created by that alignment. To be successful, Murray must rely on his peripheral vision and react to open lanes throughout the entire line of scrimmage. So if a hole opens up on the back side, he needs to see it immediately and take advantage.
Unfortunately, he's never had to do that before.
As the Cowboys' workhorse last year, the lion's share of his carries came when the quarterback was under center, as opposed to the shotgun formation. Playing behind a stout offensive front, he only needed to identify a narrow lane the line created (i.e., the hole) -- he didn't need to evaluate the entire line of scrimmage. In essence, to adapt to the Eagles' style of play, Murray must develop an entirely new skill set and adjust how he views the field.
This is virtually impossible.
Only a handful of backs can be classified as feature backs, which is to say, someone who does everything well. Most runners fall into one of three categories: one-cut, open-field or third-down.
Murray is a one-cut guy. He has a rare combination of strength and balance, with an exceptional capacity for attacking downhill. He can completely gash opposing defenses between the tackles and get the tough yards. Changing his style would require time and, most importantly, reps, which Murray just isn't getting.
Over the last three games, Murray has carried the ball a total of 21 times, hardly enough for an elite back to get into a rhythm, much less learn a new skill. It's true that other players like Darren Sproles and Ryan Mathews fit the system better, but Murray's style makes him a back with tremendous upside. That's why the Eaglesinvested $40 million in him.
In Week 5 against New Orleans, the Eagles incorporated more runs from under center. The result was one of Murray's better outings of the season (83 rushing yards and a touchdown). In order for Murray to be successful, and for the Eagles to leverage their investment, Kelly would have to completely alter the offensive approach.
The reality is that Kelly's up-tempo offense is tailored for the more elusive runners, those who can exploit gaps in the defense and maneuver around defenders to create opportunities on their own. It's not a coincidence that LeSean McCoy was successful in Kelly's system.
Ultimately, that's not who Murray is -- and it doesn't appear that Kelly is willing to change his offensive scheme. As a result, there isn't a dire need for him in the Eagles' system. So despite the guaranteed money (more than $20 million) they gave him this offseason, the Eagles should part ways and find a better complement to their backfield.
No matter what happens, Murray's future with the Eagles is uncertain. Should the trends I illustrated above continue, we can take his role reduction as a signal that his time in Philadelphia may be short-lived. Then again, are we sure Chip Kelly will even be back next season?