Boston (27-3) won its first NBA title in 22 years last season and has looked to be well on its way to another finals appearance, as it has opened 2008-09 with the best start in NBA history.

In a highly anticipated finals rematch on Christmas, the Celtics brought a franchise-record 19-game winning streak to the Staples Center, but the Los Angeles Lakers pulled away with a 92-83 victory, handing Boston its first loss since a 94-85 setback to Denver on Nov. 14.

Thursday's game was nip-and-tuck most of the way, and the Celtics' Kevin Garnett scored to put them ahead 81-79 with 3:57 remaining. Boston was just 1-for-7 from the field after Garnett's basket, though, and the Lakers went on a 13-2 run to finish the game.

"Give them all the credit," said Paul Pierce, who had 20 points and 10 rebounds but was scoreless in the fourth quarter. "We just have to play better down the stretch."

Boston really had trouble with Los Angeles' defense, finishing with its lowest scoring effort since its loss to the Nuggets. The Celtics, who had averaged 120.0 points in their previous three games, have lost all three games they've played when scoring 85 or fewer points.

"It's tough when you lose against anybody," said Garnett, who finished with 22 points on 11-of-14 shooting. "We probably took a step back, but hats off to a good Laker team."

Boston shouldn't have as much trouble scoring on Friday, as the Warriors (8-22) are last in the league in scoring defense, allowing an average of 111.4 points on the season.

The Celtics beat the Warriors 119-111 on Nov. 26, as Ray Allen scored 25, Rajon Rondo had 22 and Garnett and Pierce each finished with 21. The victory wasn't easy, though, as Boston trailed by 14 points in the third quarter.

Playing in Oakland hasn't been easy for Boston either, as it lost 119-117 at Golden State last season, and has dropped four straight and 10 of 12 at Oracle Arena.

While the Celtics' loss to the Lakers was disappointing, it's nothing compared to what Golden State is going through.

The Warriors are off to their worst 30-game start since the 1999-2000 team opened 6-24, and are playing without Jamal Crawford (strained left groin), Stephen Jackson (hand), Monta Ellis (ankle) and Corey Maggette (hamstring).

Golden State learned Crawford would be out shortly before tip-off in Tuesday's 96-88 defeat in Miami, the Warriors' 16th loss in 19 games.

"I think we have to try and find the positives from this," said Golden State's Kelenna Azubuike, who had 16 points and nine rebounds against the Heat. "It's tough when you're losing but hopefully we're getting better as a team. We're giving it everything we have and I think that's all you can ask for. I think we'll get smarter as a team as the games go on."

Golden State boasts the second-best offense in the league (104.9 points per game), but it's averaging just 84.5 points on 34.4 percent shooting in losing its last two games. The Celtics have the league's second-best defense, limiting opponents to an average of 91.4 points.