NBA round-up: Defending champions Celtics power through Bucks
The Celtics improved to 9-2, two games behind unbeaten Cleveland in the Eastern Conference, while the host Bucks slid to 2-8.
Payton Pritchard scored 18 points off the Boston bench while Derrick White and former Buck Jrue Holiday each scored 15 points and Jaylen Brown added 14 for the Celtics.
"Team effort," Holiday said. "It's not easy doing it by yourself. We did it collectively."
It eased the memory of two lopsided Boston losses in Milwaukee last season.
"It's nice," Holiday said. "We got blown out twice last year so getting this win here with my family in the building is awesome."
Greek star Antetokounmpo also grabbed 13 rebounds and elbowed Brown to the floor at one point, then offered a hand to help him up only to pull it away when Brown reached for it.
The Bucks led 69-58 at half-time but the Celtics grabbed a 87-84 edge entering the fourth quarter and closed with a 9-5 run to seal the triumph, Tatum scoring seven in the crucial stretch.
"We just picked up the intensity," Holiday said of the third-quarter rally. "We came out, hit shots, not getting too ahead of ourselves and getting back to Celtics basketball."
At Indianapolis, Bennedict Mathurin scored 38 points and Tyrese Halibuton added 35 points and 14 assists to lead the Indiana Pacers over New York 132-121.
Jalen Brunson had 33 points and 10 rebounds for the Knicks, who also got 30 points and nine rebounds from Karl-Anthony Towns.
Detroit's Jaden Ivey missed a go-ahead 3-point shot with 1.2 seconds remaining and Houston held on for a 101-99 road victory.
Alperen Sengun's 27 points and 10 rebounds led the Rockets (6-4) while the Pistons had 26 points, nine assists and eight rebounds from Cade Cunningham in a losing cause.