Chip Kelly's offensive philosophy may or may not bring success to the field for the Philadelphia Eagles, that remains to be seen. But if you were looking for immediate surprises during training camp, look no further.

Veteran wide receiver Jason Avant and tight end Clay Harbor were recently assigned to spend a day practicing on defense, with Avant taking reps at defensive back and Harbor taking reps at outside linebacker. There are a couple possible reasons that these sudden changes have taken place.

The first and least likely reason being that Kelly, who mirrors Bill Belichick's philosophy of using certain players on both sides of the ball, truly intends to use Avant and Harbor on defense. The Eagles currently have enough depth all the way around at linebacker to where I doubt they would need Harbor's services at the position and Avant switching to any defensive back position at the age of 30 seems highly unlikely.

Another reason could be for the sole purpose of an emergency situation that would require their services on defense. That would be a little more plausible, but still doesn't seem likely enough.

The last, and unfortunately most likely reason, could be that there just isn't a spot for Avant and Harbor at their natural positions. Avant, who arguably has the best hands among any receiver in Philadelphia, may succumb to Kelly's new system, which places an emphasis on tight ends and speedy receivers, the latter of which Avant has always lacked.

Harbor's future has been in doubt since the Eagles' acquisitions of tight ends James Casey during free agency and Zach Ertz in the draft. When asked about his future in Philly, Harbor seemed to understand his current predicament:

“Obviously, we’ve got a lot of tight ends here. Right now, there is a good chance I might not be here, whatever. Right now, I’m just going to play as hard as I can, learn what they want me to learn and do what I can do to try to make this team and make the team better.”

While Harbor won't be remembered for much during his time in Philadelphia, it would be a shame to see Avant fall victim to the unfortunate but always inevitable business side of the NFL in the coming weeks.