"I'm always underestimated," Coleman said. "And I'm always out there with something to prove."
As staggeringly bad as the Falcons looked on offense with an 0-for-4 effort, with two turnovers, in the red zone, they were just as sublime on defense _ a major turnaround from a unit that last year allowed 6,108 yards, a franchise record.
Kerney recorded a single-game career high with three sacks. Smith had two, including a hammering of Josh McCown that caused a fumble and ended the Arizona quarterback's afternoon early in the fourth quarter. Travis Hall recovered the loose ball for Atlanta.
"Today's one of those games we all see where you anticipate something bad happening," general manager Rich McKay said. "You kind of knew that was in the cards, but the defense wouldn't let that happen."
Their performance, which helped limit Arizona to 61 rushing yards and an 0-for-4 effort, with three turnovers, in the red zone, allowed the Falcons (3-0) to remain atop the NFC South. Atlanta has a one-game lead over New Orleans and 1 1/2 over the defending conference champion Carolina Panthers, who were off this week and host the Falcons next week.
Perhaps the announced crowd of 70,534 knew Atlanta would struggle to score points after Warrick Dunn broke off a 60-yard run to the Arizona 8 on Atlanta's fourth play from scrimmage. Quarterback Michael Vick looked confused, though, on third-and-goal at the 4 as Peppi Zellner sacked him for a four-yard loss.
Jay Feely, who kicked 25-yard field goal to make it 3-0, added a 23-yarder early in the second quarter to give the Falcons a six-point lead that felt tenuous until Vick broke off a 58-yard run to the Cardinals' 28 with 2:03 remaining.
The longest run of Vick's career _ 12 yards longer than his famous overtime victory blaze in Minnesota two years ago _ was one of the few positive plays he had. Vick completed only 10 of 20 passes for 115 yards and one interception. Arizona sacked him five times by confusing the Atlanta line with a five-man defensive front.
According to Falcons offensive coordinator Greg Knapp, the Cardinals "played leverage on the corners, inside and out, trying to cause the routes to get disrupted a little bit." Those moves disrupted Vick's rhythm until Knapp called for him to run around left end for what became a 58-yard gain.
Linebacker Karlos Dansby chased him down and tackled him near the right sideline.
"I just couldn't get him out of the way," Vick said. "My mindset was to score, but they were a great defense. They tried to keep me contained. They widened the ends out. They passed guys off downfield as the receivers were running their routes. They did some things that we didn't expect them to do."
The Cardinals (0-3) are far more limited on offense than last week's opponent, the St. Louis Rams, but Atlanta still sacrificed passing yards to hold the running game in check. McCown, whom coach Dennis Green pulled after Smith's sack, combined with Shaun King to complete 25 of 32 passes for 238 yards.
Emmitt Smith, however, ran 18 times for just 45 yards, and Arizona's longest ground gain was a 12-yard scramble in the first quarter.
Coleman and the rest of the Falcons' defensive line proved too physical, particularly on his sack, forced fumble and recovery - all on one play - against McCown late in the second quarter.
"I took on the double team, and Ed Jasper - he beat his guy inside, and the quarterback had to scramble," Coleman said. "I wound up jumping in the air, but when he tried to pass and I knocked the ball out of his hands. I was finally in there. I just took me a little while."
The Cardinals stood third-and-four at the Atlanta 8 early in the second when Coleman stripped McCown again. Fellow tackle Ed Jasper recovered this time.
"I just knew they had to run a quarterback draw," Coleman said. "I told Ed, 'Just hit your guy, hit your block and squeeze it.' I seen him drop back and then try to take off, so I just tried to knock the ball out."