BOSTON - Now the Celtics are losing at home, too.

The defending NBA champions dropped their sixth game in eight tries Wednesday night, falling to the Houston Rockets 89-85 on Von Wafer’s go-ahead 3-pointer with 44 seconds left. It was the Celtics’ first loss in Boston since a Nov. 14 defeat to Denver sent them on a 19-game winning streak.

“In our last timeout, you could see it in our guys’ eyes. Like, ’Shoot, we’re going to lose this home game,”’ Celtics coach Doc Rivers said. “It bothered them. You could see that. And I was thinking ’That’s a good thing.”’

Yao Ming had 26 points and eight rebounds, clinching it on a putback with 12.9 seconds left to help the Rockets snap a three-game losing streak and a five-game road skid.

“Yao is unstoppable,” said Rockets forward Ron Artest, who scored 17 points playing most of the game in foul trouble. “Then, when you have shooter surrounding him, it’s hard to guard him. He shot right over the top. When he’s playing like that, we’re going to be tough to beat.”

Paul Pierce scored 26 points, and Kevin Garnett had 18 and eight rebounds for the Celtics, who opened the defense of their 17th NBA title with victories in 27 of their first 29 games. But talk of running away with another championship has disappeared as the people in Boston — and the rest of the league — wonder what’s happened.

“Nobody said it was going to be easy. I know, at times, we do make it look easy,” Garnett said. “We are a very, very confident team. ... I feel we have the mind-set to weather the storm.”

Wafer, starting in place of Tracy McGrady, had 12 points on 4-for-10 shooting. But he squared up for the open 3 when Aaron Brooks regained control of his dribble and made the pass into the corner.

McGrady had missed one game with a sore left knee before returning against Philadelphia on Tuesday night and struggling in the second half. Brooks came off the bench with 19 points for the Rockets, who avoided a second straight season sweep by Boston.

“Aaron Brooks made big shots in the fourth quarter,” Yao said. “ This is a big win for us, because we have a lot of respect for the Celtics.”

Glen Davis scored a season-high 12 for the Celtics.

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Houston led 62-55 early in the second half when Garnett scored on the fast break and then hit a jumper to cut it to three points. The Rockets managed just a pair of baskets, by Artest and Chuck Hayes, over the next 4 minutes while Pierce made six straight free throws and hit a 3-pointer to give Boston a 68-66 lead with 3:49 left in the third.

But Boston scored just 11 points in the fourth quarter, getting just two baskets in the first 9:17 — both by Gabe Pruitt.

Houston led 83-81 when Artest fouled out with 3:14 left. Pierce pointed him tauntingly to the sideline, while Celtics owner Wyc Grousbeck stood at his courtside seat and waved goodbye.

Pierce made a jumper to tie, it then Yao missed one of two free throws and Garnett hit Rajon Rondo for a layup that gave Boston an 85-84 lead with 1:34 to play. Garnett blocked Brooks and came down with the rebound, but Boston couldn’t score and after Brooks nearly lost the ball, he chased it down and dished it to Brooks for the 3.

Pierce missed a jumper and Brooks grabbed the rebound over Rondo. After Carl Landry missed from in close, Yao put it in to make it 89-85.

Notes: Garnett moved into 26th place on the NBA’s career scoring list, passing Walt Bellamy (20,941). ... The Celtics are 18-2 at home and 11-6 on the road.

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