The Hawks led nearly the entire way, bouncing back from consecutive home losses to two other elite teams, San Antonio and defending champion Boston. For Los Angeles, it was the lowest-scoring game of the season.
The Lakers had won five straight, locking up the top seed in the Western Conference, but an ailing Bryant had just 17 points on 7-of-19 shooting. Cleveland extended its lead for the best record to two games with a 102-74 win over Dallas.
Bryant, who missed a morning meal and film session because he wasn't feeling well, had his second straight subpar game. Coming off a 14-point performance at New Jersey, he picked up two quick fouls and had to sit out most of the first quarter.
He might have been better off just staying there, but no one stepped up to fill the void. Pau Gasol was the only other Los Angeles player in double figures, leading with 21 points, as the Lakers made just 35 percent (28 of 80) from the field.
With Atlanta struggling to make anything, the Lakers pulled to 76-68 approaching the midway point of the final period. But Bibby locked it up for the Hawks with two huge 3-pointers.
His second took the last bit of life out of Lakers, bouncing high off the rim, hitting the top of the backboard and dropping through the hoop to make it 82-70 with 5 1/2 minutes remaining.
Having already clinched the top spot out West, the Lakers suffered a setback in their bid for the best overall record
-- and guaranteed home-court advantage should they make it all the way to the finals. They also lost for the first time on a seven-game road trip, which has two games left.
With Bryant on the bench through most of the first, the Lakers struggled to 5-of-23 shooting. Los Angeles led 8-4 when their star picked up his second foul, trying to draw a charge in the backcourt just 4 minutes into the game.
Atlanta outscored the Lakers 16-5 the rest of the period for a 20-13 lead
-- Los Angeles' lowest-scoring opening quarter of the season and less than half of their 27.3-point average in the first.
Bryant returned for most of the second period, sparking the Lakers with his shooting and passing. He scored seven points, even though the Hawks tried to shadow him with little-used defensive specialist Mario West and frequent double teams.
West jawed a bit after a defensive stop on Bryant, which only seemed to fire him up. Isolated on West, he switched directions four times near the top of the key before sinking a 19-foot jumper. When the Hawks tried to double, Bryant found the open man. Gasol and Trevor Ariza both dunked off passes from Bryant.