A week after trailing by 10 points at halftime in Baltimore, the Steelers faced a 10-point, fourth-quarter deficit in Dallas.
As they had done against the Ravens, the Steelers rallied to beat the Cowboys.
"I joke I feel like I'm too old for this stuff," quarterback Ben Roethlisberger said. "But we keep winning, having fun with the guys, that's all that matters."
Roethlisberger's 8-yard touchdown pass to tight end Eric Ebron with 2:14 left in regulation achieved the Steelers' first lead and they hung on for a 24-19 victory.
Dallas' next possession ended when defensive tackle Cam Heyward and outside linebacker T.J. Watt sacked quarterback Garrett Gilbert on fourth-and-8 from the Dallas 41-yard line with 1:37 left in regulation.
The Cowboys regained the ball at their 19 with 38 seconds left after the Steelers turned it over on downs.
Dallas reached the Pittsburgh 23 but Gilbert's pass into the end zone was knocked down by free safety Minkah Fitzpatrick on a third-and-4 snap with four seconds left.
"Every time we face adversity we fight," Ebron said. "At the end of the day I wouldn't bet against us."
The Steelers improved to 8-0 for the first time in franchise history.
Game action photos from the Steelers' Week 9 game against the Dallas Cowboys at AT&T Stadium
"We're humbled and honored to be that group," head coach Mike Tomlin said. "I'm really proud of our football team. We've got a group that sticks together, a group that's mentally tough."
Dallas fell to 2-7.
Tomlin tied Marty Schottenheimer's NFL record for consecutive seasons coaching with a .500 record or better at 14.
Roethlisberger was temporarily lost to a left knee injury but only missed one offensive series.
He finished with 29 completions on 42 attempts for 306 yards, three touchdowns and a passer rating of 113.8.
The six-play drive for the game-winning touchdown covered 79 yards in 1:57.
Kicker Chris Boswell's second field goal of the day, this one from 43 yards out, drew the Steelers to within one point at 19-18 with 7:11 left in the fourth. The 11-play, 75-yard scoring drive in 4:34 began at the Steelers' 1 after an interception in the end zone by Fitzpatrick (strong safety Terrell Edmunds was penalized for an illegal block on the return).
The Steelers pulled to within 19-15 on a 31-yard touchdown pass from Roethlisberger to wide receiver JuJu Smith Schuster on the first play of the fourth (Boswell's extra point attempt was blocked).
The six-play, 75-yard scoring drive in 2:22 included completions to Smith-Schuster for 20, 20 and 9 yards prior to the touchdown pass (Ebron was penalized 10 yards for holding and the Cowboys 5 yards for offside on the march).
Dallas improved a four-point halftime cushion to 10 by turning consecutive third-quarter possessions into field goals by kicker Greg Zuerlein.
The first, from 45 yards out, increased the Cowboys' lead to 16-9 with 10:17 left in the third.
The second, a 39-yard effort with 2:13 left in the third, gave Dallas a 19-9 advantage.
The Steelers turned their final two possessions of the first half into nine points and headed to the locker room at halftime trailing, 13-9.
Boswell's franchise-record 59-yard field goal closed the second quarter.
Boswell missed wide left on a 54-yard attempt with two seconds left in the quarter but the Steelers were guilty of a false start. Boswell backed up 5 yards and this time split the uprights.
The Steelers had regained possession at the Dallas 39-yard line 52 seconds before the half on a forced fumble by nickel cornerback Cam Sutton and a recovery by Fitzpatrick.
The Steelers first got on the board on a 17-yard touchdown pass from
Roethlisberger to wide receiver James Washington 1:10 prior to intermission. Boswell missed the extra point attempt wide left and the Cowboys led, 13-6.
Roethlisberger limped to the locker room after the touchdown pass favoring his left knee.
Backup Mason Rudolph directed the subsequent four-play field goal drive and completed two of three passes for 3 yards.
The Cowboys grabbed a 3-0 lead on a 38-yard field goal by Zuerlein that ended a 12-play, 65-yard drive in 6:47 on Dallas' first possession.
The Cowboys upped their lead to 10-0 on a 20-yard touchdown pass from Gilbert to wide receiver CeeDee Lamb and a Zuerlein extra point with 7:45 left in the second. The scoring strike wrapped up an eight-play, 65-yard drive in 3:41.
Dallas turned a throwback on a punt return that went for 73 yards after an illegal block penalty had been enforced into a 44-yard field goal by Zuerlein and a 13-0 lead with 3:46 left in the second.