SAN DIEGO -- His frustration has been replaced by optimism, and his injured hamstring is finally fully recovered. So second-year linebacker Jyles Tucker has one overriding thing on his mind as the Chargers prepare to host Kansas City on Sunday.

"Point blank -- make plays," the soft-spoken Tucker said Friday. "Point blank. Seize the opportunity whenever it's there, and let's get the job done."

The Chargers' defense didn't get the job done well enough in the first half of the season, and that led to the firing of defensive coordinator Ted Cottrell last week. The unit has gone nine straight quarters without a sack -- its last one came Oct. 12 against New England -- and Tucker aspires to help end the drought.

He had three sacks in September but injured the hamstring in the final game of the month at Oakland. He missed the ensuing three games before returning against New Orleans on Oct. 26.

"I'm trying to do whatever I can do to get out there and get the job done and get some victories," Tucker said. "But as far as my leg goes, I'm feeling good.

"Now is the time to do whatever it takes. Everybody on the team needs to step into their roles and do what they need to do, and it shouldn't be any problem winning games."

Tucker stepped into the starting lineup after Shawne Merriman was lost for the season with a knee injury. He had two sacks in a mid-September victory over the New York Jets and added another one against the Raiders before suffering the injury.

October, though, was a nightmare for him. Being unable to play was pure torture, and not only on game days.

"It was the whole week, just knowing that you're not going to be able to play," Tucker said. "That hurts. That's part of the game. But now all that is behind me. I don't really even like thinking about it."

Chargers coach Norv Turner thinks last week's bye benefited Tucker.

"This extra week has given them a chance to get 100 percent and I think get some of the stamina back and some of the strength back," Turner said. "He doesn't have to play worried as the game goes on that if he starts getting tired, he could re-pull it."

Despite missing those three games, Tucker still ranks second on the Chargers in sacks behind Shaun Phillips' 3 1/2. New defensive coordinator Ron Rivera mentioned Tucker earlier this week in terms of making sure players are utilized in a manner that best suits their skills.

"We got Jyles Tucker back," Rivera said. "He's a healthy kid. We're going to let Jyles do what he does best."

That means applying pressure to the quarterback, and Tucker predicts that the Chargers will again be piling up sacks in the near future.

"Our main focus is getting to the quarterback," Tucker said. "Whatever it takes, we're going to get there."

The Rivera approach

Rivera will head the defense for the first time on Sunday, and that's when fans and observers can dissect the differences in how he calls a game compared with how Cottrell did. But the differences on the practice field and in meeting rooms are already evident.

Rivera isn't shy about voicing opinions or explaining a better way to go about things.

"The guys will tell you I'm a little bit of a nitpicker," Rivera. "I try to make a comment on everything -- every play, every practice snap. I always try to give feedback and I try to be meticulous about it and I am nitpicky."

The advice doesn't always involve something significant. Often it's about fundamentals or techniques or even attention to detail.

"The point is, are you going to correct the obvious things, or are you going to take the extra step and focus on the little details, things we're not necessarily doing wrong but we can probably do better?" defensive end Luis Castillo said. "He might say something to me like, 'You're widening a little bit on this rush and you can probably adjust your footwork a little better.' "

Et cetera

WR Chris Chambers (ankle) and CB Antonio Cromartie (hip) were listed as probable on Friday's injury report. … DT Jamal Williams (illness) missed Friday's practice; C Jeremy Newberry (illness) returned after missing Thursday's workout. … FS Eric Weddle won a friendly wager with RB LaDainian Tomlinson because Weddle's alma mater (Utah) beat Tomlinson's former school (Texas Christian) on Thursday night. The terms of the deal called for the loser to wear the other's school shirt during Friday's practice, and Weddle said Tomlinson reneged on the deal. "He's a sore loser," Weddle joked. "Sore. Sour." Tomlinson later had the Utah shirt draped over his locker room chair and said he has to keep it only "for a day." … Kansas City OLB Derrick Johnson (thigh) won't play Sunday, the team acknowledged Friday. Other Chiefs starters not accompanying the squad to San Diego include CB Patrick Surtain (quadriceps) and DE Turk McBride (shoulder).

Contact staff writer Mike Sullivan at (760) 739-6645 or msullivan@nctimes.com.