The Falcons gladly took advantage of a short-handed Chiefs defense Sunday.
Matt Ryan threw for 299 yards and three touchdowns, one of them to tight end Tony Gonzalez in his return to Kansas City, and Atlanta used a second-half surge to pull away for a 40-24 victory.
Ryan also ran for a TD, and Julio Jones caught six passes for 108 yards and two scores, both of them enjoying a Chiefs defense missing four starters due to injuries and suspension.
The Chiefs matched Atlanta most of the first half, trailing just 20-17 at the break, but a missed field goal by Ryan Succop early in the third quarter proved to be the turning point.
Atlanta scored 20 unanswered points to put the game away.
Matt Cassel threw for 258 yards and had touchdowns running and throwing, but he also fumbled deep in Kansas City territory to set up a short TD, and his two interceptions created short fields that the Falcons turned into field goals by Matt Bryant, who was 4 for 4.
There was no controversy surrounding the replacement officials. Both times that referee Mike Shepherd went under the hood for a video review, the original call stood.
Jamaal Charles had 87 yards rushing, and Tony Moeaki had three catches for 37 yards, both providing a bright spot for Kansas City. The pair of them, along with safety Eric Berry, played their first regular-season games since tearing their left ACLs last season.
Things weren't nearly as bright for the Chiefs defense, which had Pro Bowl linebacker Tamba Hali sitting out a one-game suspension for violating the league's substance-abuse policy.
Starting safety Kendrick Lewis (right shoulder), cornerback Brandon Flowers (right heel) and defensive tackle Anthony Toribio (right ankle) were inactive due to injuries, and that seemed like chum in the water to one of the league's top passing offenses.
Ryan set the tone with the Falcons' opening series, marching 80 yards behind pinpoint passing before an 8-yard pass to Jones made it 7-0 midway through the first quarter.
The teams swapped field goals before the Chiefs answered with their own TD drive.
Cassel was 4 for 4 on the series, including a 21-yard pass to Dwayne Bowe and a 22-yard TD toss to tight end Kevin Boss, who was signed in the offseason to make precisely the kind of finger-tip grabs down the seam that got him into the end zone Sunday.
The teams kept trading haymakers the rest of the half.
Ryan connected with Roddy White three times on the Falcons' ensuing drive, and a dump-off pass that Jones turned into a 14-yard score gave them the lead again. But the Chiefs had another answer when Cassel weaved his way into the end-zone from 5-yards out late in the second quarter.
Bryant added his second field goal just before half time for Atlanta, but Succop banged his own 40-yard try off the upright early in the second half - and the momentum finally shifted.
The Falcons' potent passing offense marched down field, Ryan capping the drive with a 5-yard scramble for a touchdown. Three plays later, Cassel was blindsided by John Abraham and the ball went squirting loose, and Stephen Nicholas pounced on it to give Atlanta the ball at the 7. Ryan hit Gonzalez in the back of the end zone on the very next play for a 34-14 lead.
It was the first TD scored by Gonzalez in Arrowhead Stadium since he was traded to the Falcons following a 12-year run in Kansas City. And as he'd done so many times, the former college hoops player dunked the ball over the goalpost, drawing mostly boos from a crowd that once cheered him.
Bryant added two more field goals in the fourth quarter before Shaun Draughn's late touchdown run for Kansas City made the final score more respectable.
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