The Bears lived the old saying during a harrowing three hours Sunday night using their good defense to produce the best offense.

Two Bears defenders returned turnovers for touchdowns including a 42-yard Julius Peppers return of Ben Roethlisberger’s fumble with 4:09 left to seal the 40-23 victory at Heinz Field.

That seemed to bookend Major Wright’s 38-yard interception return in the second quarter — which gave Chicago a 24-3 lead that seemed insurmountable.

The Steelers desperate and winless scored 20 of the next 23 points though.

It took a challenge from coach Marc Trestman to regain more than a touchdown’s distance.

The Bears led 27-23 with about six minutes remaining when on third down officials ruled incomplete a 17-yard Earl Bennett catch in the back left corner of the end zone.

While the Bears’ field goal team trotted onto the field Trestman threw the red flag.

Minutes later the ruling was overturned to the frustration of what was left of the crowd of 61 575.

The Bears finished with 23 points off turnovers — 13 from the two interception returns and 10 more off Steelers fumbles.

Blitzer D.J. Williams forced a Roethlisberger fumble on the Steelers’ first drive and the Bears eventually scored on a Matt Forte 5-yard run.

Chicago started the third quarter by forcing a turnover too when Wright separated Felix Jones from the ball and Henry Melton fell on it. That led to a 32-yard Robbie Gould field goal.

Melton provided one of the game’s brutal moments though when he injured his left knee in the fourth quarter and had to be carted off the field.

The Bears blitzed often usually from the linebacker spot.

Two blitzes forced a first-quarter three-and-out and took over on the 40-yard line after Devin Hester’s fair catch of a punt.Matt Forte broke off a 55-yard run on the first play rushing past Gay as he tried to strip the ball out and then tip-toeing up the right sideline before stepping out at the 5.

Pass interference on a pass to Brandon Marshall gave the Bears First-and-Goal at the one.

The team ran out their “heavy” package — with little success. Bush was stuffed on first and third down with an incomplete pass intended for Martellus Bennett in between.