The Associated Press

Keyshawn Johnson chose to sign with the Carolina Panthers for one reason, and it has nothing to do with receptions.

‘‘I didn’t come here to catch 100 balls,’’ Johnson said. ‘‘I came here because I feel Carolina is the team with the best chance to get to the Super Bowl.’’

The free-agent receiver signed a four-year, $19 million contract Friday with the Panthers, becoming the complement to Pro Bowl selection Steve Smith. The deal includes a $5 million signing bonus.

Johnson called Smith ‘‘the most dominant force in the NFL at wide receiver’’ and said he was looking forward to lining up next to him.

Johnson wasn’t the only former Cowboys player to find a new team Friday. Larry Allen, the Cowboys’ 10-time Pro Bowl guard and perhaps the most dominant offensive lineman of his generation, agreed to a two-year contract with the San Francisco 49ers.

Also, former New England Patriots tackle Tom Ashworth has agreed to a $13 million, five-year contract with the Seattle Seahawks, the Patriots re-signed fan favorite Troy Brown and the Eagles re-signed veteran right tackle Jon Runyan.

With Johnson on the field, defenses can’t zero in on Smith because they’ll know the Panthers have at least a second option. Carolina lacked that for most of the year because its running game took months to develop, and No. 2 receiver Keary Colbert had a big drop-off from his outstanding rookie season.

Though the 34-year-old Allen has played 12 tough NFL seasons, the struggling 49ers believe they could use a big dose of Allen’s famed nastiness. Allen, the massive last link to the Cowboys’ most recent Super Bowl-winning team, was released Tuesday when he refused to take a pay cut.

Despite their 4-12 record last season and a young roster, the 49ers were attractive to Allen for more reasons than money.

Brown, 34, has spent his entire career with the Patriots, who drafted him in 1993. His 514 career receptions rank second for the Patriots, 21 behind Stanley Morgan. Brown had 39 catches for 466 yards and two touchdowns last season.

The team also re-signed offensive lineman Stephen Neal.

The Seahawks nabbed Ashworth after Pro Bowl left guard Steve Hutchinson signed with Minnesota on Monday.

The 6-foot-6, 305-pound Ashworth has started 30 games for the Patriots over the last three regular seasons.

He has mostly been at right tackle since San Francisco signed him as an undrafted free agent in 2001, including in the Super Bowl three seasons ago.

Ashworth could move to guard to replace Hutchinson.

In other moves Friday:

—Defensive tackle Lional Dalton agreed to terms on a four-year deal with the Kansas City Chiefs.

—Despite a second-half collapse that ruined a shot at the playoffs, the Atlanta Falcons gave coach Jim Mora a three-year contract extension Friday that runs through 2009.

—The New York Jets re-signed veteran tight end Chris Baker.

—The New York Giants re-signed wide receiver Tim Carter.