Browns coach Rob Chudzinski said he is turning to the veteran Campbell for Sunday's game against the Kansas City Chiefs in place of Weeden, who struggled after Brian Hoyer went down with a season-ending knee injury in Week 5.
Campbell, 32, last started a game for the Chicago Bears in a loss to the San Francisco 49ers in November 2012. He becomes the Browns' 20th starting quarterback since 1999 and the team's third in 2013 as the season reaches the halfway point. He started six games for the Oakland Raiders in 2011 before suffering a knee injury.
Campbell draws a tough first assignment against the unbeaten Chiefs, who lead the NFL in sacks with 35.
Weeden, a first-round draft pick in 2012, completed only 17-of-42 passes for 149 yards with one touchdown and one interception last Sunday in a loss to the Green Bay Packers. He ranks 32nd in the league in completion percentage and 30th in passer rating.
The Browns are 0-4 in games that Weeden started this season.
---Veteran defensive end Andre Carter signed with the New England Patriots after a tryout Monday in Foxborough.
Carter, 34, had 10 sacks in 2011 but wasn't re-signed after suffering a torn quadriceps muscle. Carter played in 12 games last season with 2.5 sacks for the Oakland Raiders.
In 12 NFL seasons, Carter has played in 175 career games with 147 starts and has accumulated 517 total tackles, 66 sacks, 30 passes defensed, 15 forced fumbles and four fumble recoveries. He has registered double-digit sack totals three times in his career with a career-high 12.5 in 2002 with the 49ers and 10.5 in 2007 and 11.0 in 2009 with the Redskins.
In other player movement, defensive tackle Sealver Siliga was signed to the Patriots practice squad. Cornerback Travis Howard was released from the practice squad.
---The St. Louis Rams added two quarterbacks to their roster Tuesday when they brought back Austin Davis and signed veteran Brady Quinn.
To make room for the pair on the active roster, the Rams released offensive lineman Brandon Washington and placed starting quarterback Sam Bradford on injured reserve. Bradford suffered a season-ending knee injury against Carolina on Sunday.
The Rams also released linebacker Jonathan Stewart from the practice squad.
Davis and Quinn will be expected to serve as backups to Kellen Clemens, who was named Monday by coach Jeff Fisher as the starter.
Davis spent 2012 as the third quarterback in St. Louis and spent this summer with the Rams as well before being cut after Clemens won the battle for the backup spot.
Quinn was cut by the Jets on Monday when they activated David Garrard.
---Josh Freeman's first game as the Minnesota Vikings' starting quarterback did not go so well on the field, and the team announced he suffered a concussion that could keep him out of Sunday night's game against the Green Bay Packers.
Vikings coach Leslie Frazier said via Twitter that Freeman's status is up in the air. If he is unable to play, Christian Ponder likely would be back in the starting lineup for the home matchup against the Packers.
Freeman will be required to pass concussion protocol tests required by the NFL to be cleared for action. In the meantime, the Vikings are turning back to Ponder, who has not started since Week 3. Matt Cassel will be the backup.
Frazier said he saw no signs of Freeman's head injury during the loss to the New York Giants on Monday night in the former Tampa Bay Buccaneers quarterback's first start after signing 12 days earlier with the Vikings. Freeman struggled against the Giants, completing 20-of-53 passes for 193 yards an interception.
Freeman thinks the injury occurred during the third quarter but said he never told the team about any symptoms until Tuesday.
---The New York Giants placed center David Baas on injured reserve with a knee injury suffered in Monday night's win over the Vikings.
Baas had just returned from a three-game absence due to a neck injury when he was hurt on the final snap of the Giants' first offensive series Monday.
Jim Cordle, who started the three games Baas missed earlier this season, will move into the starting lineup fulltime.
Baas is the second Giants offensive lineman to land on injured reserve this season, joining right guard Chris Snee (hip, Oct. 4).
---Wide receiver Andrew Hawkins returned to practice with the Cincinnati Bengals on a roster exemption.