Cleveland Cavaliers guard Donovan Mitchell (45) controls the ball while Boston Celtics center Neemias Queta (88) defends during the second half at TD Garden.
Cleveland Cavaliers guard Donovan Mitchell (45) drives to the basket between Boston Celtics center Neemias Queta (88) and forward Jayson Tatum (0) during the second half at TD Garden.
Cleveland Cavaliers guard Donovan Mitchell (45) drives to the basket between Boston Celtics center Neemias Queta (88) and forward Jayson Tatum (0) during the second half at TD Garden.
Boston Celtics guard Payton Pritchard (11) shoots a three point shot while Cleveland Cavaliers guard Darius Garland (10) defends during the second half at TD Garden.
Cleveland Cavaliers guard Donovan Mitchell (45) controls the ball while Boston Celtics center Neemias Queta (88) defends during the second half at TD Garden.
Bob DeChiara/Imagn Images
Cleveland Cavaliers guard Donovan Mitchell (45) controls the ball while Boston Celtics center Neemias Queta (88) defends during the second half at TD Garden.
Bob DeChiara/Imagn Images
Cleveland Cavaliers guard Donovan Mitchell (45) drives to the basket between Boston Celtics center Neemias Queta (88) and forward Jayson Tatum (0) during the second half at TD Garden.
Jayson Tatum had 33 points, 12 rebounds and seven assists on Tuesday to help the Boston Celtics defeat the visiting Cavaliers 120-117, ending Cleveland's season-opening, 15-game winning streak.
The Cavaliers were attempting to become the second team in NBA history to start a season 16-0. The 2015-16 Golden State Warriors won 24 straight games before losing.
Al Horford added 20 points and seven rebounds for the Celtics, who made 22 of their 41 3-point shots. The Celtics also received 19 points from Derrick White while winning the NBA Cup game.
The Cavaliers were within 102-100 following a Craig Porter Jr. 3-pointer with 7:12 to play, but Boston led 110-102 after White connected on a 3-pointer with 4:23 remaining. Cleveland pulled within four when Donovan Mitchell made a trey with 24.4 seconds left, then cut its deficit to three twice, the last time being on Ty Jerome's jumper at the final buzzer.
Cleveland Cavaliers guard Donovan Mitchell (45) drives to the basket between Boston Celtics center Neemias Queta (88) and forward Jayson Tatum (0) during the second half at TD Garden.
Bob DeChiara/Imagn Images
Boston Celtics guard Payton Pritchard (11) shoots a three point shot while Cleveland Cavaliers guard Darius Garland (10) defends during the second half at TD Garden.
Bob DeChiara/Imagn Images
Mitchell had 35 points and eight rebounds in the loss. The Cavaliers received 22 points, 11 rebounds and six assists from Evan Mobley.
It was a rough shooting night for Cleveland's Darius Garland, who was 3 of 21 from the field and finished the game with eight points.
The Cavaliers played without Isaac Okoro (ankle), Dean Wade (ankle) and Caris LeVert (knee).
It was the second NBA Cup game of the season for each team. The Celtics and Cavaliers are both 1-1 in the group stage standings.
The Celtics led 26-20 after one quarter and 65-48 at halftime. Boston shot 63.6 percent (14 of 22) from 3-point territory in the first half.
Boston extended its lead to 21 points early in the second half, but Cleveland used an 18-3 run to pull within six points, 82-76, with 3:27 left in the third quarter. Cleveland whittled Boston's lead to 86-84 on a Jarrett Allen dunk with 1:19 to play in the third, but Tatum made a 3-pointer at the buzzer to give the Celtics a 93-88 advantage entering the fourth.
