INDIANAPOLIS – The speed of a Sio Moore or the power of Nate Irving.

Is that the debate the Colts have for the two lead guys competing for the open starting inside linebacker spot in 2016?

Irving is known for his run defense prowess, something he was barely able to show in his first season with the Colts.

Still recovering from a November 2014 ACL injury, Irving played in just eight games for the Colts last season (106 total snaps).

In watching film of his 2015 self, Irving doesn't like what he sees.

"I knew I was better than I was putting out there," the fifth-year pro says. "But the competitor in me wanted to go out and compete as soon as I was able to.

"I even knew that it was too soon but I just wanted to play football."

Health is no longer a concern for Irving.

With the offseason program picking up and Training Camp a little more than two months away, Irving is going to be in the mix to replace Jerrell Freeman.

D'Qwell Jackson is in search of a new running mate and has seen what a healthy Irving can do.

"I was a huge fan of Nate when he was over in Denver," Jackson says. "He was a thumper who could move around, was fast.

"The second year (post injury) is going to be where he gets more comfortable. He's not thinking about his knee, he's moving around and hopefully we see the old Nate that upstairs saw to bring him in."

It was in Denver where Irving started half of the 2014 season (before the ACL injury) for a top-five defense.

Like Jackson, Chuck Pagano is eager to watch an Irving no longer worried about his knee.

"We saw a small sample, a short glimpse of what he's capable of," Pagano says of Irving's two starts last season.

"They say eight, nine, 10 months on a ACL then it's completely healed. But until you get back out on the grass and get confidence in that thing, until you have a year under your belt and you've played and you've practiced day after day after day and the thing doesn't swell on you, and you don't have setbacks, you're never really totally 100 percent healthy. So I think he's going to enter (Training Camp) feeling the best that he's felt in a long, long, time which will give him a chance to be successful."