Insider: Critical decision looms for Colts on unheralded star Anthony Castonzo

Jim Ayello | IndyStar

Show Caption Hide Caption Colts OT Castonzo on coming off loss: 'We have to win games' Colts OT Anthony Castonzo on changing the momentum coming off a loss.

INDIANAPOLIS — Most NFL offensive lineman seem to live in two states of public perception: ignored or under fire.

Anthony Castonzo has experienced both during his nine-season NFL career, each spent protecting the blind side of Indianapolis Colts quarterbacks.

During the first couple of years of his career, the 2011 first-round pick was regarded by some as a bust, unworthy of his lofty draft selection (No. 22 overall) or a starting position even on what was then a porous Colts offensive line.

But those who suggested as much probably didn't know what they were talking about, said someone who knows exactly what he's talking about when it comes to offensive linemen.

Former Cleveland Browns All-Pro and perhaps future hall-of-famer Joe Thomas believes Castonzo, now 31, got a bad rap early in his career and as a result has gone underappreciated for far too long.

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The 10-time Pro Bowl left tackle contends that Castonzo was put in a no-win situation, protecting a quarterback (Andrew Luck) who held on to the ball for a long time while trying make big plays in Bruce Arians' offense and was therefore prone to taking sacks.

"Quarterback play and the offense you’re in has so much to do with everyone’s opinion of offensive lines," said Thomas, now an NFL Network analyst. "For a long time, Andrew Luck was in systems where he’d hold onto the ball a long time, he’d try to always make that play. So he’d get hit and get sacked a lot. And everyone would talk about how terrible the offensive line was.

"So all of these years we were really critical of that Colts line and Anthony Castonzo. Early on in his career people were saying he was kind of a bust. ... Well, maybe we should revisit that and maybe we should say maybe he was doing a better job than we had thought because of the situation he was in. I’m really happy for him because I’ve thought he’s been a good player in the NFL for a long time."

Now playing in Frank Reich's system, which encourages quarterbacks to get rid of the ball quickly, Castonzo has become one of the better tackles in the NFL — though to little fanfare.

In a way, being ignored as an offensive lineman is a compliment. If no one is talking about them, it probably means they're doing their jobs. Even Reich ignores Castonzo. Or at least he knows he has that luxury, and that is sort of the ultimate compliment.

When Reich is scheming up passing plays, he knows he can almost always chalk up a win on the left side of the line, even if that means leaving Castonzo alone on an island with a great pass-rusher.

"Developing offensive game plans, when you know you have a left tackle that can do what he does, I can’t even tell you how that changes game planning," Reich said Thursday. "He is making an impact really on every play we have.”

To say Reich completely ignores Castonzo, though, would be misleading. The coach and Colts play-caller often looks to him in the running game. According to Pro Football Outsiders, no team runs off the left end more than the Colts (19% of their rush plays) have this year.

Of course, some of Reich's confidence running left so often comes from also having All-Pro guard Quenton Nelson sharing that side of the line with Castonzo. Still, Castonzo is more than doing his part.

So far this season, Pro Football Focus has graded Castonzo as the sixth-best offensive lineman — third best tackle — in pass protection, while ranking him eighth among tackles in run blocking.

While those rankings shouldn't be taken as gospel, they certainly support Reich's assertion that Castonzo "is having a great year." That would make two in a row for the left tackle.

Last season, Castonzo was part of one of the league's best units, one that allowed a league-low 18 sacks and once kept Luck clean for 239 consecutive snaps.

This year, the line has allowed a bit more pressure — 25 sacks, tied for 8th fewest in the league — but rarely has Castonzo been the culprit despite playing all 901 of the Colts' offensive snaps this year. He's also a big reason why the Colts are sixth in the NFL in rushing yards per game (133.4) and Marlon Mack is just 100 yards shy of his first 1,000-yard season.

He also has yet to incur a holding penalty this season, either on offense or on 58 special teams snaps.

Given the success Castonzo is having in the running and passing games, it does make one wonder why he doesn't get a little more attention.

Colts center Ryan Kelly has a hunch as to why that might be.

"Probably because everyone’s talking to the guy next to him all the time," Kelly said, half-jokingly. "And you guys can’t seem to get enough about that guy."

Kelly's not wrong. Nelson is adored in Indianapolis and across the national NFL landscape for his violent play. He is one of few lineman whose highlights go viral on social media. While Nelson certainly doesn't seek the spotlight, it is often on him while talented teammates are ignored.

Castonzo, though, isn't the type to be bothered by his young teammate's higher profile, obligingly answering questions about Nelson when asked.

And ultimately, a little extra media attention won't mean much to Castonzo. What's most important to him is that he does his job in practice and on game days and that when the time comes, those abilities are properly valued by the Colts.

Castonzo's four-year, $44-million contract expires at the end of the season, making him a free-agent to-be. After the team handed out an extension to another longtime veteran, signing tight end Jack Doyle to a three-year, $21-million contract last week, one has to wonder whether Castonzo is next on their list.

Given the praise showered upon him by Reich earlier this week and Chris Ballard's long-stated desire to build a team that can win in the trenches, it seems likely the Colts are aware of Castonzo's contract situation. Whether they are eager to extend him remains to be seen.

Castonzo, too, would have to want to remain in Indianapolis for the next few years of his life and be OK with not testing an open market sure to value to his rare talents. While Castonzo spoke proudly about Doyle's contract extension, he was reticent to discuss the possibility of signing one of his own.

"I'm looking forward to these next three games for sure," Castonzo said with a smile. "We'll see what happens at the end of the year. I really don't want to think about it or talk about it until then."

Given the shortage of high-quality offensive linemen in the NFL, there's little doubt Castonzo would command a high price on the open market. But will the Colts allow him to get there?

With the playoffs now practically out of reach, these are the biggest questions facing the Colts. Who will be part of their future? Who do Reich and general manager Chris Ballard believe will be part of the core of the Colts' next championship-level team?

Castonzo has played like that type of player. Time will tell if the Colts value him in that way.

Follow IndyStar Colts Insider Jim Ayello on Twitter Facebook and Instagram: @jimayello.