So just where is all this headed for Bears?

With three weeks still left in the season, the only relevant questions regarding the Bears are: Which coaches will be fired, how far will the purge reach, and will it include general manager Phil Emery?

It's beginning to look like a total housecleaning might be in order.

Head coach Marc Trestman, who took over after Lovie Smith's last team went 10-6 in 2012, went 8-8 in his first year and appears destined to fall even further this year. But he says the support he always has felt from everyone at Halas Hall, including Emery, remains intact.

"I don't think it's ever changed here," said Trestman, whose team officially was eliminated from the postseason with Detroit's victory over Tampa Bay on Sunday.

"By all the key parties that you're thinking about. It's been tremendously supportive, during the good weeks and bad weeks. And it's been extremely consistent by everybody here.

"The only thing that people ask me here is what can they do to help. And that comes from all areas of this building. 'What can we do to help you along,' and that support has been very heartfelt."

Of course Emery has been supportive. If Trestman fails, so does the guy who hired him.

What makes the regression to 5-8 this season look even worse is that Emery had the reigning NFL coach of the year, Bruce Arians, in the building but rejected him in favor of Trestman, who had never been a head coach anywhere except in the Canadian Football League.

Arians wound up with the Arizona Cardinals, where he finished 10-6 last year in the ultracompetitive NFC West, the strongest division in the league. The Cardinals went 5-11 the year before Arians arrived.

The NFC West is even stronger this year, and the Cardinals are 10-3 despite playing without starting quarterback Carson Palmer and with journeyman Drew Stanton for more than half the season. Stanton had started four games in seven NFL seasons before this year.

Arians might not have taken the Bears job even if it was offered, considering he would have been pressured to keep some of the defensive coaches from Smith's staff.

Note to Emery if he is allowed to stick around long enough to make another head-coaching hire: Most self-respecting head-coaching candidates are not going to allow someone else to tell them who should be on their staffs.

So, while Arians has turned around a team that had won 18 games in three years before he arrived, the Bears have gone backward.

What do the Bears have to hang their hat on this season? The Week 2 28-20 road victory over the San Francisco 49ers.

Their other 4 wins have come against teams with a combined record of 15-36. The Bears also are one of just four teams the Carolina Panthers have defeated this year.

The offense, so promising in Trestman's first year, has plummeted from No. 8 in total yards to 20, from No. 5 in passing yards to 14, from 16th in rushing yards to 26th. After scoring more than 30 points six times last year, the Bears have yet to do it once in 2014.

The defense, which last year allowed more points (478) than any team in franchise history, is threatening to challenge that standard of futility, on pace for 465.

Last year's defensive failure was blamed on injuries and lack of depth. In the off-season the Bears signed four free agents who became starters, and they used four of their first five draft picks on defensive players.

Yet there is little difference between this year's crew and last year's sad-sack outfit. The one constant is coordinator Mel Tucker.

Special teams have been a sore spot all season. That's as much an indictment of Emery as coordinator Joe DeCamillis, who has had to operate with an ever-changing cast of characters because of the GM's incessant and futile shuffling of bodies at the bottom of the roster.

Mistakes and penalties have been constants throughout the season.

"It's frustrating, but it's challenging," Trestman said of dealing with his team's steady stream of self-inflicted wounds. "It's part of the job to find different ways to send the same messages and to help your guys grow and get better as football players and as a team."

The messages aren't getting through, otherwise the Bears wouldn't already have committed 91 penalties for 788 yards, already exceeding last year's totals of 82 penalties for 734 yards with three games still to play.

If the messages that Trestman and his staff are sending don't get through a lot more clearly in the final three games than they have in the previous 10 (7 losses), it'll be time to blow the whole thing up.

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