Anthony Castonzo, Quenton Nelson

Colts offensive linemen Anthony Castonzo (74) and Quenton Nelson (56) congratulate each other after a Nov. 11 win against the Jacksonville Jaguars at Lucas Oil Stadium.

INDIANAPOLIS — From many athletes, the statement would seem too self-deprecating. Too immodest. Too cheesy.

But Anthony Castonzo is not most athletes.

There's an earnest honesty about the Indianapolis Colts' 30-year-old left tackle. In fact, he tells the truth sometimes to a fault.

He also blocks outside distractions with relentless passion — including annoying details like contract negotiations.

So when Castonzo says the final year of his current deal and the accompanying talks for a second extension aren't weighing on his mind this spring, it's best to take him at his word.

“The media found out about my extension before I did last time,” Castonzo said Thursday at the Indiana Farm Bureau Football Center. “So we’ll see. That’ll be a fun one to see what happens this time.”

If there's a theme to Castonzo's spring, it's not looking back.

As he enters his ninth season in the NFL, Castonzo is the second-longest tenured player on Indianapolis' roster. Only 46-year-old kicker Adam Vinatieri — preparing for his 14th year with the Colts — has been on the team longer.

Still, Castonzo doesn't feel old — no matter how counterintuitive that seems on the surface.

He pulled his hamstring three times last season and missed the first five games. The resulting 11 starts represented the lowest total of his career.

But the Colts were 9-2 in the regular season when Castonzo was on the field, and he and rookie left guard Quenton Nelson formed an exceptionally strong run-blocking combo.

That's not why he stood before the media Thursday, however, and declared his body feels better than it did going into his rookie season in 2011.

The credit for that goes to legendary strength and conditioning coach Rusty Jones.

Castonzo battled knee pain throughout his career but never could trace the source. Jones found it stemmed from imbalances in his hips and alleviated the stress.

The veteran offensive lineman also altered his offseason workout, focusing on strengthening his base. And last season's struggles — that included a pulled pectoral muscle that sidelined Castonzo for much of the spring — actually proved to be a blessing.

“It was weird,” Castonzo said. “I had a pulled pec throughout all the OTAs last year, and then I had three pulled hamstrings. And it was like all that rest-slash-rehab, it was like when I came back I needed it. I needed to kind of reassess what I was doing with my body and reassess where I was at. And it was kind of rejuvenating.”

Thus, he's preparing for the 2019 season with a completely new perspective.

Castonzo used to attack offseason training with reckless abandon. His goal was to be in prime form for the start of spring practice, but he's since seen the folly in that thinking.

The injuries a year ago helped drive that point home. So did head coach Frank Reich's incremental improvement plan.

The Colts live by a simple motto: Get 1% better every day.

And Castonzo fully embraces it.

“I used to want to be 100% ready to go for that first OTA and be playing my best football,” he said. “That was like the world to me because every time I step on the field, I want to dominate. But now I understand that OTAs are part of the process. I want to be playing my best ball come Sept. 8 and then moving forward into the season. So it’s definitely more of a gradual thing to make sure I’m at my strongest, my fastest, when the season starts.”

Jones has suggested Castonzo could play 10 more seasons with his current health and conditioning plan.

The left tackle isn't ready to go quite that far.

Castonzo wants to play as long as he still can be an asset to his team.

For the first time in his career, he's part of an offensive line with all five starters returning. And the number of young players who made serious contributions a year ago makes it feel as though this team's championship window is wide open.

Castonzo believes if he plays well, his contract status will resolve itself.

And he's willing to keep that general philosophy for the forseeable future.

“It’s kind of weird cause I do still feel young,” Castonzo said. “I don’t feel like I’ve gotta try these tricks to get my job done. I feel like I’m still physically young, and I kind of have that same mentality.”

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