INDIANAPOLIS – The Indianapolis Colts were the only team in the NFL last season to start the same five players for all 16 games on the offensive line.

The feat took gutsy game-day decisions from left guard Quenton Nelson and center Ryan Kelly – among others – to remain intact, and it will be difficult (if not impossible) to replicate in 2020.

Depth behind the offensive line starters has been one of the more talked about weak spots during an otherwise strong offseason for the team. General manager Chris Ballard said during the draft the team is comfortable with some of the veterans still on the roster and will continue to look for additions throughout the offseason.

CNHI Sports Indiana’s Roster Review continues with a look at how the offensive tackles stack up this spring:

THE STARTERS

There are no questions at the top of the depth chart.

After mulling retirement, Anthony Castonzo signed a new two-year deal to return at left tackle. And right tackle Braden Smith is among the more underappreciated players on the roster.

Smith made the transition from guard to tackle early in his rookie season and has made 29 starts in his first two years. He’s had trouble at times with speed rushers off the edge but has proven himself to be a solid pass protector overall.

He’s also a bulldozer in the running game, where his athleticism often allows him to get to the second level and help turn good gains into big plays.

Castonzo credits Colts director of sports performance Rusty Jones with improving his overall fitness level and prolonging his career. He had arguably his finest season at age 31 in 2019 and remains an important locker-room voice for one of the league’s best offensive lines.

In the end, Castonzo said his decision to return for a 10th NFL season was not difficult.

“After having a healthy season, I kind of looked back on the season and I said, ‘Do I think that that is the best that I’m going to be able to play?’” he said after re-signing in March. “… If I had come away from that saying, ‘I think that’s the best that I can play, and it’s downhill from here,’ then I probably would have decided to retire. But after doing some offseason training, kind of getting going and thinking about things, I think that I’ve got a lot of better football and a lot more in me.

“So I decided that I want to keep playing. I mean, I love the Colts, and I love football. So it ended up being a definite decision with absolutely nothing kind of swaying me in the other direction.”

THE SURVIVOR

It seems Le’Raven Clark is a projected training camp casualty every summer. But the 2016 third-round pick is back for a fifth season despite being inactive for all 16 games in 2019.

The 27-year-old has more experience than any offensive line reserve on the current roster. He’s played both tackle spots as well as right guard and made 35 appearances with 12 starts over his first three seasons.

It’s too early to make any definitive statements, but Clark will enter the preseason as the favorite for the “swing” tackle role backing up Castonzo and Smith.

DEPTH PERCEPTION

Carter O’Donnell is among the more intriguing prospects on the roster. The 6-foot-5, 313-pound Canadian was a four-year starter at the University of Alberta and drew interest from several teams before Indianapolis signed him as an undrafted free agent. The abbreviated offseason workouts won’t help his early development, but O’Donnell could be a long-term player to watch.

Andrew Donnal is the only other tackle with regular-season experience on his resume. A fourth-round pick in 2015, he has appeared in 31 games with six starts for the St. Louis and Los Angeles Rams, Baltimore Ravens, Detroit Lions and Miami Dolphins.

Villanova’s Brandon Hitner, Texas El-Paso’s Cedrick Lang and West Texas A&M’s Travis Vornkahl are likely to compete for a spot on the practice squad.

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