Josh Smith added 23 points for the Hawks, who were ahead 61-51 at halftime and led by as many as 26 in the third quarter.
The Pistons have lost three straight, all without guard Brandon Knight, who has a hyperextended right knee. Will Bynum was also out Monday because of a suspension.
Jeff Teague had 20 points for Atlanta, which shot 14 of 33 from 3-point range. Kyle Korver scored 15 points, all from beyond the arc.
Rodney Stuckey led Detroit with 22 points, and Jonas Jerebko added 21.
Horford equaled his career high in rebounds.
Atlanta's only loss in its last six games was to Miami, and the Heat lead the Hawks by 8 1/2 games in the Southeast Division. But the Hawks are very much on the bubble for home-court advantage in the opening round of the playoffs. They moved percentage points ahead of Brooklyn for fourth place in the Eastern Conference.
The Pistons were already without rookie big man Andre Drummond, who has a stress fracture in his back, and Knight's recent injury made matters worse. With Bynum suspended for striking Indiana forward Tyler Hansbrough during a game against the Pacers on Saturday, Kim English
-- a second-round pick in last year's draft -- became the top guard off the bench.
[to top of second column]
The Hawks were without Zaza Pachulia because of an Achilles strain, but they shot 55 percent in the first half, including 7 of 16 from 3-point range. Horford already had 13 points and 13 rebounds by halftime.
Horford's shot from the baseline in the third made it 76-58, and Pistons coach Lawrence Frank took his second timeout of the quarter. It was no use. A 3-pointer by Smith pushed the lead to 24, and Teague's two free throws made it 86-60.
The Pistons cut the deficit to 14 and had the ball midway through the fourth quarter, but Teague's steal and layup made it 97-81.
Near the end, Horford capped his terrific game with a 3-pointer from around the top of the key
-- his first of the season and fourth of his career.
NOTES: Korver has made a 3-pointer in 49 consecutive games. ... Horford also had 22 rebounds against Miami on Feb. 27, 2009.
Press; By NOAH TRISTER]
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