LAKE FOREST, Ill. — Like most teams with West Coast offensive philosophies, the Chicago Bears script their first 15 plays.

The script is badly in need of a rewrite.

The Bears haven’t scored in the first quarter of six consecutive games. Last Sunday’s game was little more than a re-run. After Tampa Bay took a 10-0 lead in the first half, the Bears rallied to win, 21-10.

The Bears fell behind by 10-0 or more in five straight games, and they did all this on a full week or more of preparation time.

“It’s hard to get into a rhythm playing like that,” quarterback Jay Cutler said. “It’s happened a few times to us and it’s just unacceptable.”

Now the Bears have to go into Detroit for Thursday’s Thanksgiving morning show with only some walk-throughs and light practice from Monday through Wednesday. The Bears must extend the Lions’ two-game losing streak or Chicago can pretty much discount any playoff chances.

“We’ve all had experience in putting game plans together and knowing how much information the guys can handle going into a game without practice time,” head coach Marc Trestman said of his coaching staff. “So we put that into play and we communicate with our players as well.

“If there are things in there that could be troubling we certainly talk about as a staff because we want to be able to go out there and play fast and not have to think, at least keep thinking at a minimum and go out there and play.”

At this point, what can going into a game with almost no prep time hurt? The Bears hit a high-futility point Sunday against the Bucs by gaining only 68 first-half yards and three first downs — and one of the first downs came on a penalty.

“To me it was very easy,” Trestman said, trying to explain the sputtering start. “Dropped balls, penalties, tipped balls, all of that. As I said to the guys at halftime there was no one guy. We passed it around to everybody and you just can’t be efficient playing football that way, especially when you drop footballs and you have penalties.”

Three dropped passes and two costly penalties helped kill drives, but these are problems the Bears offense has had at the outset for six games.

Particularly alarming for the Bears were the pre-snap penalties and lack of communication in games the last two weeks, chiefly because those were home games. Now they go to noisy Ford Field against a Lions team desperate for a win after falling out of first in the NFC North.

Trestman seemed unwilling to let Cutler throw the ball downfield Sunday, so the quarterback finished with 130 yards passing but no interceptions. It was the first time in four games Cutler went without an interception.

Still, there was none of the promised moving of Cutler in and out of the pocket that was so successful against Minnesota. And when he did, the target was tight end Martellus Bennett in middle and short routes.

Bennett and wide receiver Brandon Marshall had dropped passes, and Trestman personally challenged some unnamed players in the locker room at halftime before the offense came out with a 52-yard scoring drive, then capitalized on two turnovers with TD drives of 15 and 13 yards.

No one is getting too excited about 15- and 13-yard drives, or about beating the Vikings and Bucs in successive weeks.

Still, as Cutler pointed out, “We’ll take two straight versus anybody regardless of record. I think it’s good. Gets the confidence going. Get this team believing we’re the team that started this season.”

It’s difficult to see it reaching three straight wins unless something changes in terms of offensive efficiency at the start of the game or otherwise.

“We know what they (the Lions) have talent-wise offensively and we know that they haven’t opened it up the last three weeks and it hasn’t happened for them,” Trestman said. “That will be a challenge for us coming into Thanksgiving for our defense knowing where their offense is right now, knowing that they’re close to wanting to break things wide open as well.”

REPORT CARD VS. BUCS

–PASSING OFFENSE: C-minus — Brandon Marshall and Martellus Bennett dropped passes early, and Jay Cutler wilted for a while under the pass-rush pressure when the offensive line had trouble handling Gerald McCoy. Although Cutler threw for only 130 yards, he did avoid an interception after throwing at least one in each of the previous four games. And his ability to get it into the end zone from the red zone when the Bears defense created a short field with turnovers was the offensive difference in the second half.

–RUSHING OFFENSE: C — Once the Bears broke Matt Forte for a 19-yard run starting the second half, it seemed to give some flow to the entire offense. Jay Cutler had less pressure on him when Forte became a threat. The goal-line and short-yardage running by Forte continued to be a positive after years when the Bears would always bring in a short-yardage back who usually failed.

–PASS DEFENSE: A-minus — The only negative came in the form of a few missed tackles on short passes that resulted in big gains. A season-high five sacks led to matching the season high with four turnovers forced, including two interceptions. Stephen Paea continues to enjoy his best season in a contract year at defensive tackle with two sacks. The cornerbacks handled Tampa Bay’s size at receiver well downfield, with Kyle Fuller allowing one touchdown. Young corners Al Louis-Jean and Demontre Hurst avoided breakdowns, as fill-ins for injured players.

–RUSH DEFENSE: A — Even losing Lance Briggs didn’t prevent the defensive front from holding the Bucs to 66 total rushing yards and 3.0 yards a carry. Normally losing their defensive signal caller has resulted in players being out of their assignment lanes and the defense getting gashed. Tampa couldn’t get any consistency in the running game, whether in the spread or tighter formations.

–SPECIAL TEAMS: C-minus — If there’s something that can go wrong for the Bears on special teams, it usually does. On Sunday a holding penalty on Ryan Mundy on a punt return and a false start by Christian Jones on a punt helped to spoil field position. Then Pat O’Donnell produced 20-yard and 18-yard punts at the worst possible times in the final minutes. Robbie Gould had a 54-yard field goal into the wind that was strong enough to be halfway up the upright — and it struck the upright. However, there were positives, such as Marc Mariani handling punts and kicks without incident and coverage units making plays to keep the Bucs inside their own 20 to start five drives.

–COACHING: C-plus — Marc Trestman and offensive coordinator Aaron Kromer have to get a huge portion of the blame for the offense starting slowly for the fifth straight game. They’ve trailed at least 10-0 in the last five games. Trestman did inspire some productivity in the second half by challenging offensive players at halftime in the locker room. He also deserves credit for a cautious game plan in the second half, even if it indicated his confidence in Jay Cutler to avoid an interception is just not there. Mel Tucker’s defensive game plan showed a good knowledge of where Josh McCown’s weaknesses are. The Bears applied pressure up the middle and moved around their landmarks in zone coverage. It was a simpler scheme than used in some previous games where the Bears defense succeeded, but it worked efficiently to give Lovie Smith a dose of his own medicine and produced turnovers.