Double trouble for Bears

By trading away former starter Chris Harris in training camp, the Bears made it crystal clear they were secure in their talent and depth at safety.

Now that starting free safety Mike Brown is out for the season, they'll see if their self-assessment was accurate.

By acquiring Anthony Adams in free agency and trading for Darwin Walker during camp, they fortified a defensive tackle position that had suffered a thinning of the ranks in the off-season.

The loss of starting nose tackle Dusty Dvoracek will test if they stockpiled enough talent.

Although Bears coach Lovie Smith was reluctant to admit it Monday afternoon, both Brown and Dvoracek have been lost for the season with left knee injuries. They were placed on injured reserve with ruptured ACLs in the left knee.

It marks the fourth straight year that ends in injury for Brown.

He played just 2 games in 2004 before suffering a ruptured Achilles tendon. The 2005 regular season ended with a calf injury in the 12th game, and the injury was re-aggravated in the playoff loss to the Panthers. Last season, he went down with a foot injury after just 6 games.

After Sunday's loss in San Diego, the thought of yet another season-ending injury choked up Brown as he spoke with reporters.

He wasn't the only one.

"Mike has gone through a lot," Smith said. "He's our team leader; a competitor. We all feel for him. If I continue to talk about it, I could get emotional just knowing what Mike Brown has gone through to get himself back in position to play.

"I'm concerned about him overall -- mentally (and) physically. Freak accidents happen, but it just seems like they've happened to Mike more than they should."

Dvoracek has had his own run of bad luck injury-wise as well. He suffered a foot injury in his first preseason game as a rookie last year that sidelined him for the season.

The loss of Brown and Dvoracek doesn't immediately signal disaster for a defense that played superbly Sunday, but it does severely diminish depth at both spots.

"If there was an area that was fairly strong on our football team, we would say that it was the safety position," Smith said. "We traded Chris Harris earlier. By doing that, we were saying that we had a lot of depth there.

"If Mike can't play anymore, Danieal Manning will move up into that role. He's a good football player."

Manning has much better speed than Brown but nowhere near the savvy and leadership of the eight-year veteran. Manning started 14 games last season as a rookie, when he replaced Harris after two games, but he in turn was relegated to a backup role by the off-season acquisition of Adam Archuleta.

Brown and Archuleta were extremely productive in their first game together, making several physical hits, which both have well-deserved reputations for delivering.

Brown also recovered a fumble near the Bears' goal line and had their only interception. Archuleta was second on the team with 7 solo tackles.

Now he'll be paired with Manning. Brandon McGowan, who already plays in some three-safety alignments on running downs, will move up in the rotation.

Rookie Kevin Payne, who was inactive for the opener, could see some action as well.

The $25 million that the Bears spent on a five-year contract for Walker looks like a smart investment. He'll take over for Dvoracek, who impressed with his run defense and ability to handle double-team blocks.

Walker may not be as stout against the run as Dvoracek, but his 26½ sacks over the past five seasons are fifth best in the league among tackles, and he worked well next to Pro Bowl tackle Tommie Harris on Sunday.

"We felt like we had three starters, three guys in the rotation before that," Smith said.

Adams, who was inactive Sunday, becomes the third man in the Bears' tackle rotation, and Antonio Garay is expected to be activated from the practice squad.

"Anthony Adams has practiced well lately," Smith said. "We brought him in here to play for us, so we have a little depth at both positions."

They're about to find out if they've got enough.