Al Horford's clutch play in the closing minutes helped keep the streak alive.
Horford scored 23 points, including a tying basket after Philadelphia took its first lead late in the game, and Atlanta recovered after squandering a 21-point lead to beat the 76ers 91-85 on Saturday night and stretch its franchise-record winning streak to 19 games.
It was one of the biggest threats yet to a streak that began with a win at Milwaukee on Dec. 27 and has left the Hawks with the NBA's best record.
"That was a rough game," said Atlanta's Jeff Teague, who made only three of 12 shots for 10 points. "We had to battle it out and win any way possible."
Atlanta capped a 17-0 January, the best undefeated record in a calendar month in NBA history, according to Elias Sports Bureau.
The Hawks led by 21 in the first half, but the 76ers came back to take their first lead at 83-81 on a jam by Nerlens Noel with less than 3 minutes remaining.
Horford scored to pull the Hawks even, and Dennis Schroeder's 3-pointer with 1:35 left gave Atlanta an 86-83 advantage. Following a miss by Philadelphia's K.J. McDaniels, Horford's jumper gave the Hawks a five-point lead.
The 76ers attacked with 3-pointers in the second half. They set season highs with 14 3s, including nine in the second half, and 35 attempts.
Philadelphia coach Brett Brown called the second half "a fantastic learning experience."
"You've put in a lot of work," Brown said. "Let it fly. Go ahead and get your legs into your shot, find your teammate and you will or you won't. And they did.
"And we had to, because they do such a good job of guarding the paint, that's all that was open."
Philadelphia's Hollis Thompson had 12 points while making four of six 3s.
Horford had a game-high 11 rebounds, four assists and three blocks.
"Al made a lot of big plays," Hawks coach Mike Budenholzer said. "When the game got tight, defensively he went to the boards."
Shooting problems returned in the first half for the 76ers, who ended a streak of 23 straight games below 100 points in Friday night's 103-94 win over Minnesota. Atlanta led 49-34 at halftime as the 76ers struggled from the field and free throw line.
76ers: Philadelphia finally reached 20 points with 6:06 remaining in the first half. ... The 76ers haven't won three straight since a four-game streak from Dec. 29, 2013, to Jan. 4, 2014. ... Carter-Williams had his left ankle examined following the game but said he was fine.
Hawks: Teague was a little off on an intended alley-oop pass for Kent Bazemore in the third quarter, but they liked the result. Bazemore, soaring over the rim, had to hold off at the last second as the pass went in the basket for a 3-pointer. ... Schroeder and Paul Millsap each had 15 points. .. Attendance was 19,006 for the Hawks' 10th sellout in their last 12 home games and 11th of the season. Atlanta had a combined nine sellouts the last two seasons.
Hawks veteran forward Elton Brand showed his toughness by remaining in the game after being hit in his left eye, which was red after the game. He walked off the court before turning around in the tunnel and returning to the game.
"I just forgot I was tough for a second," Brand said with a smile.
Bazemore had only three points in his first start of the season as DeMarre Carroll (left Achilles strain) and Thabo Sefolosha (right calf strain) were held out. Sefolosha, hurt early in Friday night's win over Portland, is expected to miss six to eight weeks.
76ers: At Cleveland on Monday.
Hawks: At New Orleans on Monday.
Information from The Associated Press was used in this report.
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