Roethlisberger finished 19 of 29 for 250 yards and three scores in all, including a 9-yard strike to Brown in the third quarter and a 47-yard dart to the All-Pro wide receiver early in the fourth as Pittsburgh (2-2-1) put together its most complete performance of the season.
Brown caught six passes for 101 yards. His two touchdowns gave him 64 in his career, moving him past Hall of Famer John Stallworth and into second place on the franchise's all-time TD reception list.
James Conner ran for 110 yards and two scores and added 75 yards receiving for Pittsburgh, which improved to 7-0-1 all-time against the Falcons (1-4) at home.
Matt Ryan passed for 285 yards and a touchdown but was also sacked six times and spent the final minutes of Atlanta's third straight loss on the sideline with the game out of reach. Pittsburgh cornerback Joe Haden kept Falcons star wide receiver Julio Jones in check. Shadowing Jones -- who entered the game leading the NFL in yards receiving -- all afternoon, Haden held Jones to five receptions for 62 yards, all of them coming in the fourth quarter with Atlanta well behind.
There were no such problems for Conner, whose breakout day helped the Steelers break out of their early-season funk. The second-year back was limited to just 19 yards rushing on 11 carries in a loss to Baltimore on Sunday night. The going was considerably easier against the NFL's 28th-ranked defense.
Conner piled up 99 total yards in the first quarter alone, but the Steelers led just 13-10 at the break thanks in part to Roethlisberger and Brown's failure to get into a rhythm.
Brown came in averaging just 9.4 yards per reception -- well below his career average of 13.4 -- but brushed off the idea that he and Roethlisberger are having communication problems, joking that their "Wi-Fi" was a little off kilter but would soon start humming again.
It didn't look that way at the end of the first half, when Roethlisberger heaved the ball off his back foot into a double-covered Brown in the end zone. Atlanta's Damontae Kazee easily picked it off to keep Atlanta within striking distance.
It didn't last. Roethlisberger capped a 12-play, 85-yard drive in the third quarter with a bullet to Brown. Roethlisberger gave an exaggerated fist pump in the aftermath as if to say "finally" as Pittsburgh went in front 20-10. Steelers All-Pro fullback Roosevelt Nix then blocked a punt by Atlanta's Matt Bosher, and Nix served as a lead blocker on Conner's 2-yard scoring sprint that put the Steelers up 27-10.
Ito Smith bulled over from 2 yards with 12:28 remaining to get the Falcons back within 10, but Pittsburgh responded immediately.
Roethlisberger hit Brown in stride down the left sideline and Brown did the rest, racing across the goal line with his longest reception of the season and quelling -- for the time being -- the seemingly nonstop drama around one of the NFL's most enigmatic teams.
Falcons: Welcome Tampa Bay to Atlanta next Sunday. The Falcons have won the last three meetings with the Buccaneers.
Steelers: Travel to AFC North rival Cincinnati next Sunday. Pittsburgh swept the season series from the Bengals last season.
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