Allen Park — In some ways, the Lions treated Tyrunn Walker like a rookie during their offseason program.
After three years with the Saints, Walker is learning a different defensive scheme and, as a result, didn't spend much time with the Lions' first-team defense, even though there's a good chance he's the second-best option at defensive tackle after Haloti Ngata.
Walker, however, isn't focusing on the depth chart. He started one game for the Saints, but was still a coveted free agent this offseason.
"I don't look at depth charts, I never did," Walker said. "I never will. I'm just coming out here and doing what I've got to do to get each other better. If I'm worried about the reps and depth chart, then I might not be doing something I need to be doing on the field."
Walker has overcome plenty of hurdles, but his football acumen became apparent when he started playing as a junior at Westgate High School in New Iberia, Louisiana, after his basketball coach convinced him to play.
As a senior, Walker was an all-district defensive end. The college offers, however, never came because Walker struggled academically — he said his grade-point average was between 2.0-2.5.
Walker received a scholarship from Jones County Junior College in Mississippi. Then, in his second year, he accepted a scholarship to play at Tulsa even though offers from Iowa State, Mississippi and Mississippi State came later in the year.
At Tulsa, Walker had 25.5 tackles for loss and 13.5 sacks in two seasons. But he went undrafted in 2012, which led him to sign with his hometown Saints.
As a rookie, Walker didn't appear in any games as he learned to play tackle, but he thought his ability to avoid the practice squad as an undrafted player was a good sign.
"It taught me how to be a pro, how to go and follow a routine and do the things I needed to do to be successful," he said. "It made me better. It made me hungrier."
Walker played in seven games his second year, but missed much of the season with a knee injury. Then in 2014, he carved out a considerable role, playing all 16 games with one start. His numbers weren't gaudy — 19 tackles, one for loss, one forced fumble and 2.5 sacks — but he made an impact. Pro Football Focus ranked him the 21st-best defensive tackle.
But the cash-strapped Saints couldn't afford Walker's tender as a restricted free agent for $1.5 million and offered him less than $1 million, leading him to look elsewhere.
"It was what it was," he said. "Yes, that's home, but this is my job."
With more than a dozen teams interested, he visited the Patriots, but didn't sign with them.
"No disrespect to the Patriots, but that Super bowl last year — and I'm sure they feel the same way — is last year," he said.
Walker's next visit was with the Lions, and while in Allen Park, he said he spoke with coach Jim Caldwell for nearly 45 minutes.
Caldwell said Walker's ability to play multiple positions and move well at 6 feet, 3 inches and 294 pounds was impressive, but he also thought highly of the player's intellect.
"The coaches that he's worked with before said he knows every single defense, every position, where everybody's going, and I think that happens because of the fact that he has a pretty good insight into defensive football," Caldwell said.
Walker said he liked the Lions' scheme, which is more aggressive than the Saints', which has defensive linemen reading the defense.
"Out here (with the Lions) it's just straight attack," Walker said. "You line up and just go, so it's kind of like slow pace to fast pace."