The Chicago Bears couldn't make enough stops and Jay Cutler committed some big mistakes.

Sounds familiar, doesn't it?

A revised defense came up short, Jay Cutler made some questionable decisions, and the Bears dropped the season opener to the Buffalo Bills 23-20 in overtime Sunday.

"The season's going to start clicking off here pretty soon," Cutler said. "Games will start rolling up, we're going to get into a rhythm. We'll watch this (Monday) and we'll move on."

This was not the sort of start the Bears had in mind after missing the playoffs six of the previous seven years.

They made big changes to a defense that ranked among the worst in franchise history last season, signing five-time Pro Bowl end Jared Allen and adding some other key players. They believe they have the stoppers to support a prolific offense that returned intact. But they'll have to do better than this.

Fred Jackson set up Dan Carpenter's field goal in overtime with a 38-yard run to the 1. The veteran ran for just 61 yards, but he came through with a big one at the end.

"I am old, but I can still play," the 33-year-old Jackson said.

The Bears had just punted to open the extra period and Buffalo took over on its own 22 to start the winning possession. The Bills got the ball to the Chicago 39 when the 33-year-old Jackson turned toward the left side and broke off his big run, pushing safety Chris Conte out of the way twice inside the 10 before being knocked out of bounds at the 1.

Buffalo's EJ Manuel backed up 3 yards and put the ball in the middle of the field. After a delay of game, Carpenter won it with a 27-yarder.

It was a good start for the Bills as they enter a new era following the death of founding father and Hall of Fame owner Ralph Wilson. They're trying to end a 14-year playoff drought and they started by knocking off a team eyeing a run to the postseason.

"It's so difficult to win on the road in this league, especially on opening day I think it's even tougher," Marrone said. "I'm proud of them. It was different, I'm not going to lie to you. It was different in that locker room before the game."

Chicago got little pressure from a revamped defense despite the addition of Allen, and Cutler got picked off twice while throwing for 349 yards and two touchdowns.

The Bears trailed 17-7 at the half after Buffalo scored 17 unanswered points and came up short down the stretch after tying it.

The Bills looked like they might pull this one out in regulation with a 20-17 lead after Carpenter kicked a 33-yard field goal.

That came after Cutler threw across his body and tried to squeeze a pass to Martellus Bennett on a third-and-1 at the Buffalo 34. Kyle Williams came away with his first career interception instead.

But the Bears answered after the Bills grabbed the lead.

They drove from the 20 to the Buffalo 19, and Cutler threw an incomplete pass to Brandon Marshall in the end zone before Robbie Gould tied it with a 37-yard field goal with 30 seconds left in regulation.

"You guys are going to be as negative as possible," a surly Cutler said. "But we've got a lot of games left, we did a lot of good things. Obviously we made mistakes today and we've got to clean them up and got to keep it going."

Manuel completed 16 of 22 passes for 173 yards for Buffalo. He also had a 2-yard touchdown run in the first quarter.

Robert Woods added 78 yards receiving.

Chicago's Matt Forte ran for 82 yards and had 87 receiving. Brandon Marshall caught eight passes for 71 yards and a touchdown. Alshon Jeffery also had 71 yards receiving, although he spent most of the second half on the sideline because of a hamstring injury.

It wasn't a great afternoon for a revamped defense, either. Allen, the star addition in the offseason overhaul, was a nonfactor. But coach Marc Trestman thought it was a good day overall for that group — Jackson's long run aside.

"At the end of the day you keep them in the 17 to 20-point range, that should be enough for us to win," he said. "And if we hang onto the football, take care of it, we would have been in a good position to do that."

NOTES: Trestman thought Jeffery might return at some point in the second half, but that didn't happen. ... Slauson and Garza did not think they were seriously injured. ... Bills LB Keith Rivers left the game because of a groin injury and S Aaron Williams was being evaluated for a concussion afterward. Buffalo also held out CB Stephon Gilmore because of a nagging groin injury.


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