Cavs down Bucks to improve to 8-0, Thunder unbeaten in West
Garland drilled a step-back three-pointer to put Cleveland up 113-111 with 45 seconds to play, then fed Jarrett Allen for a dagger layup as the Cavs, who led by as many as 19 in the second quarter, matched the franchise's best start to a season.
They did the same in 1976.
"It's hard to get one (win) so eight is crazy," Garland said.
The Bucks, with two-time NBA Most Valuable Player Giannis Antetokounmpo a late scratch with an adductor strain, dropped their sixth straight game, coming up short again after a one-point home loss to the Cavs on Saturday.
Milwaukee point guard Damian Lillard scored 14 of his 36 points in the third quarter as the Bucks battled back to lead 91-89 heading into the fourth.
They pushed the lead to eight points midway through the fourth but couldn't hold off the Cavs.
Evan Mobley added 17 points and Allen finished with 14 points, 15 rebounds and a massive block on Lillard with 8.8 seconds to play that sealed the win.
"We had to fight for 48 minutes," Garland said. "We knew they were going to come out in the second half and try to be more aggressive."
The Oklahoma City Thunder remained the only unbeaten team in the Western Conference, downing the Orlando Magic 102-86 to improve to 7-0.
Jalen Williams scored 23 points, Shai Gilgeous-Alexander added 21 and for the fifth time this season the Thunder held their opponent to fewer than 95 points.
On a busy night that saw every team in action, the Detroit Pistons upset the Los Angeles Lakers 115-103 while the reigning champion Boston Celtics romped past the Hawks 123-93 in Atlanta.
The Golden State Warriors welcomed Stephen Curry back from a three-game injury absence with a 125-112 victory over the Wizards in Washington.
In Detroit, Cade Cunningham scored 17 points with 11 rebounds and 11 assists for the third triple-double of his career and Jaden Ivey scored 26 points to power the Pistons to their third win of the season.
Anthony Davis scored 37 points for the Lakers but was troubled by a left ankle injury in the fourth quarter.
He stayed in the game and threw down an alley-oop dunk that cut the Pistons' lead to five points with 4:10 to play but Detroit pulled away again.
LeBron James scored 20 points with eight rebounds and 11 assists, but the Pistons seized the lead in the first quarter and remained in control the rest of the way.
The Warriors led all the way in Washington, Curry scoring a team-high 24 points in his first game since he tweaked his left ankle on October 27.
Durant lifts Suns
Jayson Tatum led the way for Boston with 28 points. Derrick White added 21 as the Celtics again barely missed injured star Jaylen Brown.
In Phoenix, Kevin Durant scored 35 points including a driving layup with 24 seconds left that proved the game-winner in the Suns' 118-116 victory over the Philadelphia 76ers.
Six Phoenix players scored in double figures as the surging Suns spoiled nine-time All-Star Paul George's injury-delayed debut with Philadelphia after he signed with them as a free agent in the off-season.
Sacramento's Domantas Sabonis was the hero in Miami, grabbing an offensive rebound and making the game-winning put-back basket with seven-tenths of a second remaining in the Kings' 111-110 victory over the Heat.
In Denver, NBA MVP Nikola Jokic's triple-double of 28 points, 14 rebounds and 13 assists fueled the Nuggets in a 121-119 victory over the Toronto Raptors.
The Utah Jazz, who opened the season on an 0-6 losing streak, grabbed their first victory, 135-126 over the Bulls in Chicago.