"It was a difficult decision," Hurney said. "There were several guys we were considering but we only had one tag. In the end, we decided to use it to keep our offensive line intact."
While Hurney said he'd like to keep all three players, Kalil will be offered a one-year, guaranteed contract worth more than $10 million, a big boost from the $550,000 base salary he earned in 2010.
If the current franchise tag rules remain under the new labor deal, another team could sign Kalil only by surrendering two first-round draft picks to the Panthers. Carolina could also match a team's contract offer and keep Kalil.
One of Carolina's second-round choices in 2007 out of Southern California, the 25-year-old Kalil became a starter a year later. He quickly emerged as a key cog on the line along with fellow Pro Bowl left tackle Jordan Gross, left guard Travelle Wharton, and right tackle Jeff Otah, who missed all of last season with a knee injury.
But the move means Carolina will have to compete to keep the 24-year-old Johnson, who had a breakout 2010 season after Julius Peppers left in free agency. Johnson finished with 11 ½ sacks after managing 10 combined in his first three NFL seasons. Placing the franchise tag on Johnson would've cost about $13 million.
Johnson, who recently spoke with Rivera, said he hopes to stay in Carolina.
"I hope I do. I've been here forever it seems and I don't want to relocate," Johnson said. "I think we've had some success and will have more in the future."
Hurney and his staff arrived in Indianapolis on Tuesday for this week's scouting combine.
Hurney insisted they wanted to keep their core, which would include Williams, who combined with Jonathan Stewart in 2009 to become the first set of teammates in NFL history to each rush for more than 1,100 yards.
Williams, Carolina's career rushing leader with 4,211 yards, got off to a slow start last season and managed just 361 yards on 87 carries before being sidelined for the final two months with a foot injury. The Panthers have Stewart and Mike Goodson, who emerged late last season, under contract through 2012.
Williams turns 28 in April. A one-year deal under the franchise tag would've cost about $9.5 million.
"We've said we are putting an emphasis on keeping our core players and we plan to try hard to keep each and every one of them," Hurney said.
The Panthers have plenty of work to do with the 2011 roster with 28 players from last year's team set to become free agents. Owner Jerry Richardson has said they won't sign any players until there's a new labor deal.
The current agreement expires next week, and the owners could then lock out the players if there is no progress in negotiations. That would delay free agency's scheduled start on March 4.
Copyright 2011 by The Associated Press