The foundation of an impressive but hypothetical defense could be built using just the players the Chicago Bears have had to do without this year because of injuries.
Against the San Francisco 49ers on Sunday, outside linebacker Pernell McPhee (shoulder), lineman Mitch Unrein (knee) and nose tackle Eddie Goldman (hip) were the latest casualties.
Unrein has been placed on injured reserve, where he joins safety Quintin Demps, who went to I.R. after three weeks, and outside linebacker Willie Young, last year's sack leader who played just four games.
Inside linebacker and captain Jerrell Freeman went on I.R. after just one game with a torn chest muscle and concussion, and he later was suspended for failing a PED test.
The 49ers game was the first one back for inside linebacker Danny Trevathan, who missed the previous three games with a calf injury.
A week earlier, safety Adrian Amos, who was having his best season, suffered a hamstring injury that kept him out of the 49ers game. Amos hasn't practiced this week, and neither have McPhee or Goldman.
A week before Amos was hurt, outside linebacker Leonard Floyd suffered a sprained knee and also landed on I.R.
If neither Goldman nor Amos can suit up Sunday against the Bengals in Cincinnati, the Bears would be without five opening-day starters.
Defensive coordinator Vic Fangio was able to hold the group together for a while. As recently as Week 10, the Bears ranked in the top 10 in several defensive categories, including total yards, passing yards and first downs allowed.
But the cumulative effect of mounting injuries has taken a toll. After 13 weeks, the Bears' defense is top-10 in only sacks per play.
"Frustrating?" Fangio asked. "A little bit. It seems like the last three weeks or so it's been one right after the other. It's been a little trying, but one man's misfortune has given some of these other guys opportunities. Hopefully we'll be able to play through that."
Last week's injuries left Fangio in a predicament the likes of which he only has experienced one other time in 31 years as an NFL coach, including 18 as a defensive coordinator.
Outside linebacker Lamarr Houston and safety Chris Prosinski were signed off the street midweek and played almost every snap Sunday. Prosinski played all 75 snaps, while Houston was on the field for 67 plays.
"I think one other time (I've seen) where two guys came in the building on Thursday and basically played every play on Sunday," Fangio said. "Those guys did a commendable job to be put in that situation."
With the constantly changing depth chart, Fangio has been challenged to keep in mind the strengths and shortcoming of multiple players in myriad combinations.
"You put a guy in there, and you know there are certain things that he really is not capable of doing from a mental-assignment standpoint," Fangio said. "Sometimes you're not always aware when he's in there, in combinations where they haven't been in for a long time -- or ever. I need to be aware of who's in the game more so than ever."
When everyone is healthy, the Bears believe they've got a top-10 defense. But it's difficult to say how good they are, since the defense hasn't been at full strength since Week 1.
"I think we've come close to maximizing them at times," Fangio said. "At times, we haven't. But a carpenter never blames his tools. He just finds a way to get the thing built. So we've got to go."
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