The Chiefs picked up cornerback Ricardo Colclough, who played in 36 regular-season and six playoff games with Pittsburgh since entering the league in 2004; and David Macklin, who started 75 of the 116 games he played at Indianapolis, Arizona and Washington. He was in the Rams training camp last summer.

Also signed Wednesday was DE Wallace Gilberry from the Giants practice squad.

Activated from reserve lists were Kevin Robinson, a wide receiver and kick returner who was a sixth-round draft pick from Utah State, and Michael Merritt, a tight end drafted in the seventh round.

Robinson had been on the physically-unable-to-perform list since Aug. 26 while recovering from an offseason surgery. Merritt, who remained unsigned through training camp while recovering from a collegiate injury, was placed on the non-football injury list shortly after signing.

The Chiefs now have all 12 of last year's draftees on their active roster.

Kansas City moved four players off their roster Tuesday, and picked up a fifth spot with Larry Johnson on the suspended list for this week's game.

Running back Kolby Smith was placed on injured reserve after he sustained a season-ending knee injury last Sunday against Tampa Bay.

With punter Dustin Colquitt ready to return to the lineup after missing the previous two games with a groin injury, Kansas City cut his replacement, Steve Weatherford.

The Chiefs also released cornerback Tyron Brackenridge, who they signed only last Thursday after he played in 13 games for the team in 2007.

The Chiefs also released tight end John Paul Foschi, who had played primarily on special teams.

PLAYER NOTES

--FS Jarrad Page missed a second day of workouts Thursday with a groin injury and must be considered questionable for the Chargers game. Page played last week with the same condition after taking only limited reps during the week.

--S DaJuan Morgan sustained a thigh injury in the Wednesday workout and was limited in Thursday's practice. The Chiefs are counting on him to play if starting FS Jarrad Page can't go on his groin injury.

--DT Glenn Dorsey has yet to make an impact in the pass rush, which is what the Chiefs were hoping to get when they made him the fifth player taken in the draft this year. But coach Herm Edwards defended Dorsey on Thursday, saying his gap control play in rushing defense has been solid, especially in two-gap situations similar to the system he played at LSU.

--LB Donnie Edwards, who returned to the starting lineup last week against Tampa Bay after missing three games with a high ankle sprain, is finally getting as healthy as he has been since the opening of training camp. He made 10 tackles, seven solos, in his first game back as a starter last week.

--WR Dwayne Bowe set a Chiefs rookie record with his 164-yard receiving game on eight catches against the Chargers last year at Qualcomm.

--QB Tyler Thigpen, after throwing a Pick Six among his three interceptions in his first NFL start Week 3 in Atlanta, now has thrown 83 consecutive passes without a pick. He's thrown for three touchdowns and caught a pass for another, and has a 102 passer rating in his last two starts.

--RB Jamaal Charles, after the first 100-yard game of his NFL last week against Tampa Bay, will start this week against San Diego while Larry Johnson serves his one-game NFL suspension.

--CB Patrick Surtain will miss a second consecutive game against San Diego with a quad injury.

--CB Brandon Flowers, who missed much of Tampa Bay's second-half comeback with a hamstring injury, is expected to play against San Diego.

--LB Derrick Johnson will not play against the Chargers, and may miss a few games beyond that after injuring a hamstring against Tampa Bay.

--CB David Macklin, who is familiar with the Chiefs Cover Two defensive system after playing in the system under Tony Dungy at Tampa Bay, likely will be active this week for San Diego despite joining the Chiefs only on Wednesday.

GAME PLAN: Staying close on the road in San Diego will be essential. The halftime leader has been victorious in 15 of the last 19 Chiefs-Chargers games, though the Chiefs rallied from 10 down to win at Qualcomm last year. Kansas City must use all weapons in the arsenal -- the spread, the "Wildcat," and some new wrinkles that haven't been see yet -- to get the run-pass balance that controls the ball and keeps top-rated passer Philip Rivers off the field.

Defensively the Chiefs aren't getting any pressure on anybody, so the key is limiting run-after-catch yardage against the Chargers. San Diego hasn't run especially well with LT hurting, so the Chiefs might not have to put a safety down in the box. That should help in coverage.

MATCHUPS TO WATCH: Chargers WRs Chris Chambers, Vincent Jackson and Antonio Gates vs. Chiefs secondary. With new corners (veterans David Macklin and Ricardo Colclough) having joined the Chiefs just this week as backups to rookie starters Brandon Flowers and Brandon Carr, Philip Rivers and his receivers will have every opportunities to make big plays.

INJURY REPORT: Starting LB Derrick Johnson (hamstring) won't play. Veteran CB Patrick Surtain (quad) is out. Starting CB Brandon Flowers took a full turn Wednesday despite injuring a hamstring against Tampa Bay and is expected to play.