BOSTON - What looked like an easy Saturday for the Boston Celtics turned into a fight to the finish.
It's something they've got to clean up heading into the postseason.
Kyrie Irving just missed his second straight triple-double with 30 points, 11 rebounds and nine assists, and Jaylen Brown scored 23 points with a key 3-pointer for Boston, but the Celtics had to hold off the Atlanta Hawks, winning 129-120 after blowing a 25-point second-half lead.
"To be mature about having the lead, you've got to keep the pressure on them and keep playing smart basketball on both ends of the floor," Irving said. "We didn't do that."
Marcus Morris had 19 points and Jayson Tatum scored 18 for Boston (43-27), which has won six of its past eight games.
Trae Young led the Hawks (24-46) with 26 points, John Collins added 20 with 11 rebounds, Taurean Price had 17 points and Vince Carter scored 16.
Irving had the second triple-double of his NBA career in Thursday's win against the Sacramento Kings.
It may prove to be a costly victory for the Celtics after forward Gordon Hayward strained his neck early in the game and didn't return. Hayward banged his head into a shoulder of Atlanta's John Collins, who was setting a screen, and appeared dazed before he went to the locker room.
Celtics coach Brad Stevens said Hayward was "woozy" from the hit and was sent home after halftime.
After Boston squandered the 25-point lead, Brown nailed his 3 from the right corner, sparking a 9-0 spurt that gave the Celtics a 121-112 edge with 3 1/2 minutes left.
"For our group, it's just making sure we keep our focus throughout even when the game is supposed to be out of reach," Boston's Al Horford said. "This proves any team can get into it."
The Celtics held their large lead late in the third quarter but got just one basket in 7 1/2 minutes - on a three-point play by Tatum - as the Hawks outscored them 28-6 to cut it to 109-106 on Young's 3-pointer with 7:25 to play.
Atlanta tied it at 112 on two free throws by Kent Bazemore.
"We've been doing that a lot throughout this year. We get down big, then we have to fight our way back into the game," Young said. "I think what happened today was we ran out of gas."
Boston led by 12 at halftime and went on a 15-3 run midway into the third to push its lead to 103-78 on Irving's step-back 3-pointer from the left wing, but Atlanta had a 14-2 spree late in the quarter, slicing it to 105-92.
"To be down (25) in the third and to tie the ballgame up is a testament to the guys in that locker room - young, old, whatever you want to call them," first-year Hawks coach Lloyd Pierce said.
There was an interesting - and crowd-pleasing - point-guard matchup between Irving and Young, Atlanta's promising rookie, in the first quarter. Irving scored 12 points, mostly on drives and jumpers, and Young went hard at the veteran and hit a deep 3 as he finished the period with nine points.
"To have that competitive spirit, I love it," Irving said. "If someone scores at me, I'm going right back at them."