"I wanted to be a little bit more aggressive," Pierce said. "Especially with Ray out, [I wanted] to pick up some of the slack and get us going."
Rajon Rondo scored 17 with eight assists for Boston, which also won its first 12 home games in 1984. Led by the Big Three of Larry Bird, Kevin McHale and Robert Parish, that team went to the '85 NBA Finals.
Garnett, Pierce and Allen are leading the Celtics' efforts to hang another banner in the new Garden, but they are without Allen for a game or two because of a sore right ankle. Instead, Tony Allen started and scored 11 with four steals while holding Michael Redd to seven points.
"I thought Tony Allen was a spark tonight guarding Mike," Bucks coach Larry Krystkowiak said. "I think that's one of the reasons Tony was in the lineup, to bring his energy."
Redd is averaging 24 points this season, and he hadn't scored seven points or fewer since 2004.
"Tony was awesome," Celtics coach Doc Rivers said. "Mike Redd, he's an All-Star. That's a tough matchup. If someone looked at the stat sheet you'd see 3-for-7. But if you had a game ball, you'd probably give it to Tony Allen."
Garnett played just 29 minutes for the Celtics, who pulled away when they outscored Milwaukee 32-15 in the third quarter.
Boston will try to set the offical team record for home wins to start a season Wednesday against Detroit.
The Celtics turned a five-point deficit with 3:22 left in the second quarter into a 46-44 halftime lead. But it was in the third when they really pulled away.
They scored 12 consecutive points early in the third to turn a 49-48 Bucks lead into a 60-49 advantage, then added a 10-0 run near the end of the quarter to make it 78-57.
"The lead was eight and all of a sudden it got to 20," Redd said. "So we've got to play near-perfect basketball to beat them at their home."
For the second straight game -- but just the second time this season -- the Celtics were without their regular starting five. Allen is expected to miss a game or two with a sore right ankle that he has been trying to play through for eight games.
According to Elias Sports Bureau, the Celtics' franchise record for home wins to start a season is 17, set in the team's 1957-58 season. During the 1950s, many NBA games were played at neutral sites and two neutral site losses the Celtics suffered that season are not counted by Elias as home losses.
On Nov. 28, 1957, the Celtics were designated the road team while the New York Knicks were the home team. The game was played in Philadelphia at Convention Hall in a game the Celtics lost. Additionally, on Dec. 12 of the same season, the Celtics were the road team while the St. Louis Hawks were the home team. This game was also played at Convention Hall and was also a loss for Boston. ...
The Celtics are undefeated when leading after three quarters, but they've lost both games they trailed after three. ... Boston is 7-0 on Friday nights. ... Rondo was scoreless in Wednesday night's game against Sacramento. ... The Bucks fell to 2-11 on the road and 2-6 in December. ... Pierce was 9-for-9 from the line, and the Celtics were 26-for-28.
Information from The Associated Press was used in this report.