Dave Birkett

Detroit Free Press

BOCA RATON, Fla. - The Buffalo Bills chose not to tender defensive tackle Stefan Charles as a restricted free agent this off-season, leaving the door open for the Detroit Lions to sign him to a one-year contract earlier this month.

But Bills general manager Doug Whaley said at the NFL owners meetings today that Buffalo's hands were tied when it came to letting Charles go.

"Can’t pay everybody," Whaley said. "It’s just, if you look at what we’re doing and what we got our money tied up in, we got our money tied up with a lot of good starters and backups and you got to pick and choose. That’s just the nature of the beast these days."

Charles played 13 games and made one start as a rotational defensive tackle for the Bills last year, but seemed to fall out of favor when Rex Ryan switched to a 3-4 defense.

At 6-feet-5 and 323 pounds, Charles is considered an above average run defender, but Whaley, who signed Charles off the Tennessee Titans practice squad in 2013, said he's developing as a pass rusher, too.

"I look at it this way" Whaley said. "He’s got a tremendous upside, but he’s a hard worker. Very diligent about his craft. And he’s a guy that’s big and massive and if you’re looking for a guy that can play against the run and has got potential as a pass rusher, that’s him."

The Lions paid Charles like they expect significant contributions from him this year ($1.75 million) despite returning their top four interior linemen from last season.

Haloti Ngata and Tyrunn Walker are projected to start at defensive tackle this fall, with Charles, Caraun Reid and Gabe Wright potentially in the rotation.

"If you look at him physically, the height, weight, speed and just the power and the leverage he plays with," Whaley said of Charles. "And he hasn’t played that long coming from Canada, so he’s got to get exposure so he’s going to get better and better."

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter@davebirkett.

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