Smith returned to Atlanta’s lineup after missing one game with a sprained left knee. All five starters scored in double figures, with Al Horford adding 16 points and 11 rebounds.
Kyle Korver had four 3-pointers and 16 points. Devin Harris had 15 and DeShawn Stevenson scored 12.
Goran Dragic had 21 points and eight assists for the Suns, who have lost three straight and five of six. The Suns fell to 7-27 on the road.
The Hawks took the lead for good early in the second period and had the advantage in double figures most of the second half.
Jermaine O’Neal scored 18 points for Phoenix. Markieff Morris had 15 points and 11 rebounds. Michael Beasley had 10 points.
Hawks 7-foot center Johan Petro sank a 3-pointer with less than a second remaining in the first quarter. It was only Petro’s second 3-pointer in 12 attempts in his eight NBA seasons. His first 3 came last season with the Nets.
While Petro celebrated his rare long-distance shot, the Suns made a long pass to Markieff Morris, who beat the buzzer with a 21-foot jumper.
Stevenson closed the first half with another buzzer-beating 3-pointer to give the Hawks a 57-46 lead.
Jeff Teague missed his second straight start with a sprained left ankle. Harris was the fill-in starter at point guard but Teague had eight points in 22 minutes.
Backup guard Dahntay Jones, who spent the last two days answering criticism of his late-game defense on Kobe Bryant in the Hawks’ win over the Lakers on Wednesday night, made his first appearance with 4:46 remaining.
Bryant sprained his left ankle when he landed on Jones’ foot after missing a last-second jumper.
NOTES: The teams split the season series. The Suns beat the Hawks 92-87 in Phoenix on March 1. ... Dragic had 10 of the Suns’ first 14 points. ... Korver’s second-quarter 3-pointer gave him 3s in 58 consecutive games, the NBA’s longest active streak and the league’s longest since Peja Stojakovic’s 62-game run in 2008. ... The Hawks wore their 1990s throwback uniforms.