Rookie free agents Luther Robinson (left) and Carlos Gray (74) are fighting for a roster spot with the Packers. Credit: Mark Hoffman

By of the

Green Bay — Based on a collegiate stat sheets and paychecks, free agents Luther Robinson and Carlos Gray shouldn't stand a chance to play their way past fellow rookie Khyri Thornton and onto the Green Bay Packers' 53-man roster.

Thornton, the sixth 3-4 defensive end drafted, was selected in the third round. His signing bonus was $563,250.

"I don't know about that," Mike Trgovac, the defensive line coach, said Monday when asked if Thornton had the edge. "They're all in there battling."

Thornton has been unimpressive, to say the least. Meanwhile, the pair of overlooked, unsung bit players out of the Atlantic Coast Conference has defied all odds to at least make general manager Ted Thompson think twice come cut-down Saturday.

"They've got two free agents that are better than Thornton is," said one personnel man, referring to nose tackle Mike Pennel and Robinson. "There's no question. You can throw Gray in that conversation compared to 94 (Thornton), too.

"There's no indication Thornton can play the game. Somewhere somebody saw things in him, but he's just standing there. No sign of aggressiveness. Lacks effort."

Now that Letroy Guion is back from a hamstring injury, he would join Mike Daniels, Datone Jones, Josh Boyd and probably Pennel as locks. B.J. Raji would have made six before he tore his biceps.

That leaves Thornton, Robinson and Gray fighting for one, maybe two berths. However, the fact that linebackers Mike Neal and Julius Peppers also can play down might mean there are just six jobs to be had up front.

"It's going to be hard on Ted and them to let guys go this year," said Jones. "Those guys are really good. Draft status don't mean nothing here, as you can see."

Playing for Southern Mississippi in Conference USA, Thornton played 50 games (28 starts), made 116 tackles (30 for loss) and had 5½ sacks.

Contrast those numbers to Robinson's at Miami: 33 games (three starts), 40 tackles (two for loss) and no sacks.

Now contrast them to Gray's at North Carolina State: 23 games (six starts), 35 tackles (4½ for loss) and 2½ sacks.

There weren't any big-time players ahead of Robinson and Gray, either. Each got lost in the shuffle, victims of a coaching change two years into their careers and their own ineffectiveness.

"I don't even want to think about Miami," said Robinson, who spent two years under Randy Shannon and three under Al Golden. "I'm here now and trying to be successful."

This wouldn't be the first time that a defensive lineman stuck in a rotation at a BCS school went on to better things in the NFL.

Toughness has always been an underrated quality at the position. Some players, and Thornton could be one, don't want to trade blows and head-butts with burly guards like Josh Sitton and T.J. Lang every day.

Robinson's tough-guy attitude was evident immediately in camp.

"I got that from my dad," said Robinson. "You can't take nothing from nobody. You back off and you'll be going home."

Robinson, 6 feet 3 inches and 303 pounds, wasn't among the 450 undrafted players swooped up within minutes of the conclusion of the draft. Green Bay and Washington phoned a few days later, offering a weekend tryout.

Because the Packers called first, Robinson came here. After the 72-hour cattle call, he was offered a three-year contract without a bonus.

When tackle Bryan Bulaga discussed Robinson, he mentioned pass rush, and so did a personnel man. Trgovac brought up his intelligence.

Interior rushers are hard to find and Robinson, who ran a 5.04-second 40-yard dash and bench-pressed 225 pounds 30 times, demonstrates quick hands and legit power.

Robinson chalks up his football agility to three years as the starting basketball center at Westwood High in Fort Pierce, Fla. He was planning on a career in hoops until the night his opponent in the paint was Larry Sanders, who would be drafted in the first round by the Milwaukee Bucks.

"You know how that ended," Robinson said with a hearty laugh. "That's when I realized I wasn't a basketball player."

Robinson, who missed the 2011 season with a broken foot, played up and down the line in Miami's 3-4 and 4-3 fronts.

"He (Thornton) doesn't look at it like he's drafted so he's already on the team," said Robinson. "The money doesn't matter. I'm just trying to play a game that I love."

What do Cleveland quarterback Johnny Manziel and St. Louis tackle Greg Robinson have in common with Gray?

Well, they were among the handful of third-year sophomores that bolted for the draft in January with two seasons yet to play.

"It was just a hard decision I had to make," Gray said with little elaboration. "I was ready to go."

Recruited by coach Tom O'Brien after spending a year post-high school in military school, Gray made the adjustment to new man Dave Doeren in 2013.

"I really didn't have that (college) experience as far as fun," he said. "We kept getting coaching changes. If I had stayed two more years I believe things would have been different. (Injuries) was what I was thinking."

Gray (6-2½, 311) also was a three-year starter in basketball for Pinson Valley High in Alabama, where the team went 31-3 his senior season.

"They both can move their feet," said Trgovac. "Carlos is just kind of doing it on natural instincts right now. Once he starts learning the ins and outs of the position he could really take a good jump."

Do Robinson and Gray meet the NFL standard at the position for making a team?

"I would say they're progressing to that standard," Trgovac replied. "They're all good candidates. Obviously, you want to keep going with them."

Thornton, Robinson and Gray. Active roster or 10-man practice squad, all three could be calling Green Bay home.