The Bears -- who had four turnovers -- picked up where they left off last season when they led the NFL with 44 takeaways and finished with nine defensive touchdowns, one shy of the league record.
Problem was Chicago's offense couldn't do a thing for the better part of three quarters.
Carolina's second-year cornerback Josh Norman had two interceptions, including a 60-yard return for a touchdown against Matt Blanchard.
"Certainly we didn't do what we wanted or up to our expectations," Trestman said of his offense. "... We've got work to do."
Cutler bounced back to complete 6 of 8 passes for 56 yards, but the Bears offense managed only a field goal in the first three quarters.
Newton's night was a mixed bag.
Carolina's third-year pro played three series and was 3 of 6 for 16 yards with the one touchdown to LaFell on a crossing route.
But what had been a mostly positive night turned sour when Newton threw into double coverage and was intercepted near midfield by Bostic, who ran untouched to the end zone.
Newton didn't return to the game after that.
Newton said he asked coaches to put him back in for one more series after what he described as a "disgusting" throw.
"It's something that you have to live with," Newton said. "You have to live and learn and it's keeping me anxious for our next preseason game."
Barner scored on a 5-yard touchdown run late in the first half to give Carolina a 14-10 lead at the break.
"That's unacceptable," Barner said of an earlier fumble in his NFL debut. "I can't have that. In no way, shape or form can you win games with turnovers. I've got to get that corrected."
Edwards, who has been praised by Rivera for his play in training camp, caught two passes for 38 yards.
Carolina's much-questioned secondary performed well.
Norman, entering his second season, started in the team's nickel defense and his interception of Cutler set up Carolina's first touchdown.
"I'm calmer this time around as opposed to my rookie year," Norman said.
Cutler, who said the Bears didn't do much in terms of game planning, called it an unfortunate start.
"I have to put the ball on Alshon's (Jeffery) other shoulder," Cutler said. "We had some good stuff after that; we had some bad stuff. Typical preseason game."
Typical regular season game for Chicago's defense though.
Copyright 2013 by The Associated Press