Philadelphia Eagles are counting on several key veteran players in 2015

The Philadelphia Eagles report for 2015 Training Camp on Saturday, Aug. 1. Bleeding Green Nation is already breaking down the Philadelphia Eagles roster in a position preview series, but we're also going to be running a countdown series that's more geared towards unique thematic angles. We start that series by taking a look at the veterans on Philadelphia's roster.

Longest Tenured Eagles

The Eagles released two of their longest tenured players earlier this offseason when they cut Trent Cole and Todd Herremans. Now long snapper Jon Dorenbos is the team's longest tenured player. He joined Philadelphia in November 2006.

Roles

The Eagles are counting on a number of veterans as key contributors. Dorenbos and punter Donnie Jones are obviously a big part of the special teams unit.

Philadelphia's offensive line is anchored by the 33-year-old Jason Peters at left tackle. The future Hall of Famer is still playing at a high level but one has to wonder how much left he has in the tank. Peters is a freak athlete so there's reason to believe he can last longer than others.

The Eagles got slightly younger on the offensive line by releasing 33-year-old Evan Mathis, but they seem to be replacing him with 31-year-old Allen Barbre so it's not as if the move made a huge difference. The team is really confident in Barbre for some reason.

It'll be interesting to see how the Eagles use Darren Sproles now that DeMarco Murray and Ryan Mathews have been brought in to create a 1-2 punch. Sproles spent time during spring practices working with the wide receiver group, so maybe he'll be utilized more as a pass catcher. Sproles will still be a weapon as a punt returner.

Miles Austin was a weird addition by the Eagles. Philly gave the injury-prone Austin $1 million guaranteed. It seems like he was brought in for his veteran leadership. It remains to be seen how he fits in the rotation.

Brent Celek is probably still the team's starting tight end despite Zach Ertz being a more gifted receiver. This could be the year Ertz overtakes Celek in playing time. Celek still has the advantage of being a better blocker, especially in the run game.

The Eagles surprised some by offering a contract extension to DeMeco Ryans this offseason. The Eagles are already stacked at inside linebacker with the starting duo of Kiko Alonso and Mychal Kendricks. Ryans' leadership is still valued by the team, however.

Last year as an Eagle?

Dorenbos and Jones are both under contract in 2016 but they will be 36 entering next season. They're certainly approaching retirement age.

If the Eagles feel Darren Sproles is expendable after this season, cutting him will only cost $1 million in dead money. The same goes for DeMeco Ryans.

Brent Celek can be cut for a savings of $5 million with no dead money after this season. The veteran is still a good blocker but he's hardly a threat as a pass catcher anymore.

Average age

According to Football Outsiders, the Eagles had the sixth oldest roster in 2014 when it came to snap-weighted ages. The team's average age was 27.0. Philadelphia's offense ranked 11th oldest (27.2 years) while the defense was slightly younger at only 13th (26.9). The Eagles' special teams unit ranked as the oldest in the NFL (26.9 years).

Over 30 club

The following Eagles players are 30 or older. I've included each player's years of NFL experience in brackets.

35

LS Jon Dorenbos [13]
P Donnie Jones [12]

33

OT Jason Peters [12]

32

RB Darren Sproles [11]

31

OG Allen Barbre [8]
WR Miles Austin [10]

30

DE Brandon Bair [3]
TE Brent Celek [9]
LB DeMeco Ryans [10]