Keith McKenzie replaces Daniels and Todd McMillon takes over for McQuarters, with Reggie Austin getting a promotion into McMillon's nickel corner spot in passing situations. All three are convinced they're ready to assume the added responsibility.
As a seven-year veteran, McKenzie isn't overwhelmed at being thrust into the starting lineup.
"I've been here before," McKenzie said. "It's not like it's my first time starting in a game. I did it the last two years in Cleveland. I'm ready to step in.
"Phillip is going to be missed, but he'll be back in a couple weeks. I'm just going to step in and hold it down until he gets back. That's why they brought me here, and that's the job I told them I was ready to do. When somebody's tired or somebody goes down, I'm ready to step in and hold it down until that person's ready to come back in the game."
McKenzie had eight sacks a year for three straight years from 1998-2000, but he suffered a fractured ankle last season against the Bears in the seventh game and left Cleveland for what he saw as an ideal situation.
"For me, it was an opportunity for me to come to a good team, get a chance to heal from my injury and get a chance to play without having that pressure to come in and be a starter," the 6-foot-3, 273-pounder said. "When I feel like I'm completely over this and there's no problems then I'll look toward starting. That's down the line. Right now I'm just worried about getting a chance to play."
Daniels' sprained ankle provides McKenzie that opportunity.
McMillon played extensively in the season opener, but last year he played in just eight games, mostly on special teams. In 2000, he was active for just three games after spending 11 games on the practice squad. But McMillon spent three years in the Canadian Football League and a year in NFL Europe.
"It was hard as far as zone coverages and zone principles," McMillon said of his adjustment to the NFL from the CFL, which plays mostly man-to-man coverage. "It was a big ordeal for me because it was hard for me to adjust after being up there for three years and playing a certain style and then having to come down here and learn different techniques. I'm glad they were patient with me and put me on the practice roster the first year and they let me grow."
McMillon, who will be 28 later this month, believes he's grown into the role that he'll have to play Sunday. He's played enough football and been with the Bears long enough to handle the adjustment.
"It's really no pressure," said McMillon, a clothes model in the off-season, who has done work for the Gap in the past. "We prepare for this, and you know with a long season like this, people are going to go down. That's how I got to play last year (when Walt Harris was injured in the next-to-last game. You know your roles when people go down. It helps that I played last week so much and last year, NFL Europe, everything. It comes down to this. I have to step up."
Obviously McMillon has been listening to Greg Blache. The Bears' defensive coordinator says he'll lose sleep this week worrying about Falcons quarterback Michael Vick's many talents, but not the lack of talent among his own backups.
"I look at Keith as a good solid professional. He'll have a lot more going for him because he's started games in the league before," said Blache, who has similar confidence in McMillon and Austin. "Those guys are Bears, we expect them to go play like a Bear.
"We tell them, when you get that jersey and we make them a part of this football team, you move up a notch. You've got to go get ready to play. We trusted them enough to give them a position, and we trust them to go out and play."
Sunday they get their best chance yet to earn that trust.