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INDIANAPOLIS –As we move further back in the Colts defense, the experience grows.
The Colts linebackers enter 2015 with the addition of a key veteran and an injury question to the franchise's all-time sack leader.
Here's a look at the linebacker burning questions heading into the team's offseason program.
- Where do the Colts turn if Robert Mathis isn't healthy to begin the 2015 campaign?
On the offensive side of the ball, the health of Gosder Cherilus is the major injury to watch.
Defensively, it's Mathis and his rehab process from the Achilles injury.
There's clearly no definite answer on when Mathis will return to his normal self (or how effective he will be when he does return).
If he can get back to his normal level, that would understandably enhance what the Colts have off the edge in 2015.
Let's say the worst case scenario for Mathis does happen and he can't return completely until the second half of the season.
The Colts have prepared themselves for such a situation with the addition of Trent Cole.
If Mathis can't go, it looks like the starting outside backers would be Cole and Erik Walden.
Jonathan Newsome would fit into that mix as well after a strong rookie season, where he was used primarily as an edge rusher.
This is obviously a big third season for Bjoern Werner as his role in this crowded outside linebacker group is a bit of an unknown entering the offseason.
STAT TO NOTE: In his last 92 games, Trent Cole has recorded at least one quarterback hurry in 90 of those contests.**
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- Does Jonathan Newsome see a growing role in his second NFL season?
Newsome's emergence at the end of the 2014 season is definitely something to build off going into 2015.
His strip/sack in the AFC Divisional Round of the playoffs in Denver was the type of defensive play that was missing for much of last year.
The 2015 playing time for Newsome is going to increase but it will be interesting to see how much.
The health of Robert Mathis will obviously play into that. I'd expect third-down packages to implement multiple edge rushers with Newsome being a part of those packages.
It's just one season, but there's no denying that Newsome showed the ability to make the Colts think they might have found another elite pass rusher.
One area that should help the Colts pass rush in 2015 is they have a couple of guys who will warrant much more individual attention from opposing blocking schemes (guys like Newsome/Trent Cole, and possibly Mathis). That wasn't the case in 2014.
STAT TO NOTE: Jonathan Newsome's 6.5 sacks in 2014 were the most for any rookie defensive end/outside linebacker last season.**
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- Who will be the Colts starting inside linebackers in 2015?
When free agency began last month, it appeared to be a foregone conclusion that D'Qwell Jackson and Jerrell Freeman would be the Colts starting inside linebackers in 2015.
Some inside linebacker depth was certainly needed but finding a starting caliber player there didn't seem like it would be a fit.
That changed as the free agency period reached the end of Week Two.
The Colts signed Nate Irving, who was the Broncos starting inside linebacker to begin 2014 before tearing his ACL at the midway point of the season.
When Irving's rehab from his ACL injury concludes, he will compete for a starting job at the inside linebacker position.
Irving is known as a linebacker who excels against the run, an area the Colts certainly want to upgrade in 2015.
Now, Irving will be at an obvious disadvantage if he can't get on the field until sometime in Training Camp. If he doesn't initially earn a starting job, Irving could easily play situationally early in 2015.
With a rotating trio of Jackson, Freeman and Irving in 2015, the Colts have definitely upgraded their inside linebacker depth while adding some flexibility for snap counts there this season.
STAT TO NOTE: D'Qwell Jackson's 138 total tackles last year were the most in the AFC.
