Bradley Beal scored 44 points but the Washington Wizards were still beaten in Boston, losing 140-133 to the Celtics.
Boston have now won nine in a row and are two games ahead of the Miami Heat at the top of the Eastern Conference.
Though the home side did not have an individual scorer to match Beal, they were helped to victory by Kemba Walker's 25 points, 23 from Jayson Tatum and 22 from Jaylen Brown.
If the Celtics are on a high from a near-faultless opening to their season, the opposite is true for the 2-7 Wizards.
This was Washington's third straight loss and their sixth in seven games, and they lie second last in the Eastern.
Houston's James Harden scored 47 points as the Rockets beat the Los Angeles Clippers 102-93 and moved up to second place in the Western Conference table.
It was the fifth straight win for the Rockets, in a game where Harden shot seven of 13 on threes, grabbed six boards and had seven assists.
The game was closer than the score might suggest, though.
With just minutes to go, Kawhi Leonard put the Clippers into an 86-85 lead, but Harden responded by converting a driving layup and then drilled a three-pointer to put Houston back in control.
LeBron James was in sparkling form as the Los Angeles Lakers hammered the Golden State Warriors 120-94.
James scored 23 points while his 12 assists included an array of half-court and behind-the-back passes, before he was able to sit out the fourth quarter with his team home and dry.
The Orlando Magic made the fourth quarter really count against the Philadelphia 76ers.
Playing without All-Star Joel Embiid – out with a sore knee – the 76ers were outpointed 32-15 in the final stanza and lost 112-97 to the Magic.
Nikola Vucevic, with 25 points, was the highest scorer on the night, while Aaron Gordon added 18 points, 13 rebounds and seven assists.
Elsewhere, the Charlotte Hornets lost 117-119 at home to the Memphis Grizzlies, the Minnesota Timberwolves won 129-114 over the San Antonio Spurs and in Portland, the Trail Blazers lost 106-114 to the Toronto Raptors.