The mountain of a man they call Pot Roast goes off on the Raiders, the Broncos and everyone else who passed him over in free agency: “They made their decision and they’ll have to live with it.”

ASHBURN, Va. -- Did the weight create the wait? Terrance Knighton can’t help but wonder when he considers the tepid response he generated in free agency this spring. The run-stuffing former Broncos defensive tackle surprisingly lasted longer on the market than expected and received only a single offer he deemed remotely acceptable, a one-year prove-it deal in Washington, where he has the opportunity to earn a modest $4-million-plus in 2015.

Was the big man seen as too big a risk for a big-money contract—call it Albert Haynesworth syndrome—or did his usual 340-pound girth have less to do with it than a mentality within the league that continues to de-emphasize run-stoppers in favor of pass rushers? Either way, the mountain of a man they call “Pot Roast” has a beef with the rest of the league now. The newest moniker he answers to is “the biggest steal in free agency,” a label that motivates Knighton and just might pay off handsomely for Washington this season.

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“Yeah, I was [the biggest steal],” Knighton said Tuesday, after going through the paces of another Washington OTA session. “But I’ve always bet on myself. I consider myself a premier player in this league, and I’ve got a lot of football left. This will be my seventh season, so when I hit the table again, there won’t be any excuses next time.”

Considered one of the most consistently productive players at his position, Knighton started 32 games in his two seasons in Denver and drew rave reviews for his work in helping the Broncos make a Super Bowl run two years ago. But he knows that concerns about his weight may have impacted his free agency options, and he was among those puzzled by the lack of interest Denver showed in re-signing him, not to mention Oakland, which is now coached by his former Broncos defensive coordinator, Jack Del Rio.

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“Yeah, maybe my weight was an issue for some, but my thing is turn on the tape,” Knighton said. “There have been plenty of big guys. I’m not the first big guy to come through this league. You’ve got Vince Wilfork, you’ve got Casey Hampton. All these types of guys who have been big and successful and got big contracts. But turn on my tape. There are guys at my position in this league who make more money than me, but who can’t fit into my shoes.”

Though Knighton didn’t say it, one of those players may be the guy Del Rio and the Raiders targeted in addressing their interior defensive line needs: former Cardinals defensive tackle Dan Williams, who earned a four-year, $25 million deal from Oakland in free agency, including a hefty $15.2 million guaranteed. That contract dwarfed the money Knighton ultimately received, which fell far short of the $8 million per year that he reportedly was seeking as free agency opened.

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Did Knighton, 28, price himself out of his own market, or were teams worried that a sizable payday would lead to both his body and his game getting softer, the way Haynesworth’s monster $100-million seven-year contract ($41 million guaranteed) with Washington in 2009 so famously led to the demise of his career? If there was any linkage there, it’s not applicable now, and needless to say, the always outspoken Knighton doesn’t understand that potential concern.

“I was surprised [by Oakland], but they went a different way,” he said. “They made their decision and they’ll have to live with it.”

But the reality this spring is Knighton is working out with his new team with noticeably more weight on his massive frame, and that has brought the issue of his size back around. He says he intends to be down to 350 pounds by training camp and into the 340s by the regular season—he’s listed at a laughable 331 on the Washington roster—but is thought to currently weigh in the high 360s or even 370. That won’t work long-term, and it perhaps helps explain why the Broncos didn’t fight to re-sign him, with at least one Bleacher Report story claiming earlier this year that Knighton had been fined hundreds of thousands of dollars in recent seasons due to weight-related issues.

Knighton said he played in the range of 350 pounds last season in Denver, but his effectiveness did not waiver no matter what the scale said. He played 48 percent of the Broncos' defensive snaps and according to Pro Football Focus posted a defensive stop on 8.5 percent of his run snaps last year, good for 11th best among defensive tackles. Denver’s run defense was stout in 2014, allowing 79.8 yards per game.

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​Though he excelled on third downs during the Broncos' run to the Super Bowl in 2013, Knighton became almost exclusively a two-down player last season as his contract year unfolded. He does not believe there was any coincidence behind that development.

“To make it clear, last year in Denver I didn’t play third downs just because I think for contractual reasons,” he said. “That’s absolutely what happened. My first year in Denver I played on third down. When we made that Super Bowl run, when guys were hurt, I was one of the only stars left on the D-line, and I was out there on third down and I led the charge. So I proved I can play on third down, but there’s a lot of politics involved. I’m just happy to be in Washington.”

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Never one to tip-toe with his words, Knighton has said he believes Denver is willing to make anyone expendable, as long as it has Peyton Manning at quarterback. Manning allows the Broncos to look for corners to cut elsewhere on the roster.

“I said that before and I mean it,” Knighton said. “When I say things, that’s how I feel. And they feel as long as they’ve got No. 18 at quarterback, everybody else will fall in line, you know?”

Washington could be the benefactor of the questions that surrounded Knighton’s free agency, and he was definitely the bargain basement centerpiece acquisition of a significant defensive line upgrade in D.C.—which also included the signing of free agent Stephen Paea away from Chicago and Ricky Jean-Francois after his release by Indianapolis. With the return to health of defensive end Jason Hatcher, Washington’s 3–4 front should be much stouter under first-year defensive coordinator Joe Barry.

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“I was actually surprised he was available,” second-year Washington head coach Jay Gruden said of Knighton. “We didn’t play Denver last year so I didn’t get a big look at him on tape, but I remember from the playoff run they had two years ago and he was damn near unstoppable in there. He’s got great hands and it’s very tough to sustain a block with him. He sheds blocks extremely well.

“It was a surprise to see him on the market, but when we put the film on, he looked fine to me, so we were excited to get him. He’s a unique guy because he’s such a wrecker in the run game. It’s just hard to find those guys. ‘Yeah, go ahead and run up the middle against him. Now it’s second-and-eight, so good job.’”

Knighton’s weight is at least enough of an issue in Washington for the team to reportedly tie about $450,000 of his salary to his compliance with specific weight clauses. Gruden said Knighton is working with the team’s dietician and strength coach, and is taking positive steps in battling the bulge.

“Maybe teams were worried he got too big and maybe teams were off of the big defensive linemen, because a lot of them want to go smaller up front and rush the passer,” Gruden said. “It depends on a team’s need. The problem with a big man like that is, how much base offense are you seeing? He’s known for being a big run-stopping guy, but a lot of teams are doing a spread-out passing game so often.

“But yeah, his weight, that’s big. I’m more worried about him personally, for him to be in life-after-football shape, and to be able control his weight. He’s doing a good job and taking a lot of good steps. But a lot of it’s up to him. I think he can do whatever he wants to do, because he’s that type of guy. He’s a tough-minded guy, and if he doesn’t handle it, we’ll make sure we help him and try to get him down to where we need to.”

Knighton said his mission this year is clear. He intends to provide veteran, winning leadership in Washington and play his way back on the field on third downs, because “that’s where the money is made” in the NFL. Gruden does not discount that possibility, saying “I’ve seen him do it when he was with Denver. He was on third downs in the playoffs games I saw, and he was effective there. But obviously stamina has a lot to do with it.”

Knighton said while he played as low as 325–330 pounds during his final of four seasons in Jacksonville in 2012, he loses too much strength if he drops below 340. “I’m just naturally a big guy, a 340–350-pound player,” he said. “But I’m a special type of 350 in that I can move like guys who are 300 pounds.”

Knighton’s confidence already has infused Washington’s defensive line room, and Chris Baker, his fellow defensive lineman and near life-long friend from their days growing up together in Hartford, Conn., said Knighton's athleticism will surprise everyone.

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“People don’t believe because he’s so big now, but he was a 250-pound all-state receiver in high school,” said Baker, who helped recruit Knighton to Washington, even lobbying for him to come to D.C. via a social media campaign he started. “They don’t make those any more. For a guy his size, you don’t see anybody who can carry the weight that he has and be able to move his feet the way he can. A guy who weights 350 should not be able to move the way he moves.”

Knighton’s next big move comes next spring when he’s again eligible for free agency. Will he have changed the narrative by then with the results of his prove-it season in Washington? By his own account, there will be no excuses next time, or lingering unanswered questions. There is both money to be made and a point to prove this year.

“This is a good group we have in the defensive lineman room,” Knighton said. “We’re going to be fast and physical on the defensive side of the ball, and I’m just here to dominate that line of scrimmage like I’ve been doing the past three years, bringing some leadership and showing these guys what it takes to get to that next level and play in the Super Bowl.”

Let Knighton come anywhere close to meeting those lofty goals, and his profile will again be on the rise, with a resume that speaks for itself.