Bears in a rush to improve defensive line

The defense was supposed to be the backbone of the 2008 Bears, but that hasn't always been the case through the first seven games.

The defense has been dominant at times but disastrous at others, often coming up small at crunch time.

"We've had ups and downs," defensive coordinator Bob Babich said. "At times, we look very good. Then there are times we don't; so consistency is a big thing we need to take care of."

It all starts upfront on the defensive line, and that's also where the problems start and where improvement must be made starting next Monday when players return from the off weekend.

"At times we've played well, and at times we feel like we could play a little better," coach Lovie Smith said of the defensive line. "When you're in a heavyweight fight, most of the time the champion doesn't win seven straight rounds - it's more like 4-3, and you see who can take another step. We expect our defensive line to take another step the second half of the season."

If the line doesn't take at least a couple steps forward, the Bears could be knocked out of the playoffs before they travel to Houston for the final regular-season game. It's possible the Bears' only way into the playoffs will be as champions of the NFC North, where they are currently tied with the Packers at 4-3, a game ahead of the 3-4 Vikings.

Wild-card possibilities don't appear promising, considering that 10 NFC teams, including the Bears, could be 4-3 or better after this weekend. Subtract four division winners, and that leaves six teams vying for two wild-card berths.

While the D-line has contributed to the Bears' superb work in stopping the run, it has not supplied the pass rush that was expected. The Bears are No. 26 in sacks, and the team leader, Alex Brown, has just 3.

No player on the team has more room for growth than defensive tackle Tommie Harris, whose performance last week was his first of the season that resembled the Pro Bowl level he played at the previous three seasons. Harris, who had 8 sacks last year, got his first last week.

"Tommie's a great player," Smith said. "He makes our entire defensive line better. The best game he played this year was (against the Vikings). We saw signs of the old Tommie coming back. We expect to see that and more the next time we play."

The timing of the bye week is ideal for the bruised Bears, especially the defense and specifically the secondary. Starting corners Charles Tillman (shoulder) and Nate Vasher (wrist) and nickel back Danieal Manning (hamstring) all missed the last game and did not participate in this week's scaled-back practices on Wednesday and Thursday. Neither did No. 3 cornerback Corey Graham (concussion), who may have already moved ahead of Vasher into a full-time starting job.

Smith is hopeful he'll have all hands on deck before the Bears host the Lions next Sunday.

"The next time we practice, Monday, we should have the majority of the players back, and by the time we play our next game, it's looking good for all of our players," Smith said. "We know what's at stake the second half of the season. We've gotten ourselves in position to make a serious playoff run."

Without increased production upfront, it'll be a tough race, but improved play from the D-line could kick the Bears' playoff run into a sprint.