Atlanta nearly blew a 19-point lead but held on with the help of the 10 points Horford scored in the period.
"It got a little closer than we would have liked, but that's the NBA," said Hawks coach Mike Budenholzer.
Pail Milsap added 25 points and 11 rebounds for the Hawks, who snapped a six-game losing streak on the road dating back to last season. Jeff Teague added 18 points and 10 assists.
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