HOUSTON (AP) " Yao Ming would rather not think about how close the Houston Rockets are to finally escaping the first round of the playoffs.
Yao had 21 points and 12 rebounds and the Rockets took a 3-1 lead in their playoff series with Portland, beating the Trail Blazers 89-88 on Sunday night.
Luis Scola scored 17 points and Shane Battier added 14 points and six assists for the Rockets, who snapped a six-game losing streak in Game 4s, coinciding with their 0-6 record in first-round series since 1998. Game 5 is Tuesday night in Portland.
Yao is 0-3 in the playoffs since Houston drafted him in 2002. Twice, he's watched the Rockets blow 2-0 series leads.
"We still have one more game to take care of," Yao said. "We've been in this situation before whether it is up 2-0 or ahead. My experience here is before that (clinching) game is knocked out, it's still 0-0."
Brandon Roy scored 31 points and went 13-for-13 from the free-throw line for the Blazers. Coach Nate McMillan is eager to see how his team " the youngest in the playoffs " responds to the do-or-die scenario back home.
"It's not over until they win four games," McMillan said. "We've been close in two games here, so it's a one-game season for us."
Portland led by six after three quarters and had their chances to pull out a victory in the final minute.
Houston led 87-85 when Ron Artest missed a baseline shot with 27 seconds left and Roy rebounded. Out of a timeout, Roy drove to the basket and was called for an offensive foul when he plowed into Chuck Hayes.
Houston coach Rick Adelman had inserted Hayes, a defensive specialist, only 13 seconds earlier.
"I just read him," said Hayes. "I went for it and I put myself outside the restricted area. It meant a lot. Coach needed me. Coach needed my defense."
Aaron Brooks made one free throw with 10 seconds left, but missed the second one. Travis Outlaw then missed a 3-pointer, Brooks sank another free throw and Rudy Fernandez hit a 3 with 2.3 seconds left.
The Blazers couldn't get another shot after Kyle Lowry missed two free throws with 1.2 seconds left and Portland lost at the Toyota Center for the 12th time in its last 13 games here.
The Rockets, meanwhile, have their first 3-1 series lead since they faced Seattle in the 1997 Western Conference semifinals. The SuperSonics took the next two games before Houston won Game 7.
"We put ourselves in a great position," Hayes said. "Now, we have to go out to Portland. They're going to be loud, they're going to be pumped. If we can go out there and get the series over with, so a couple of guys can get some rest, that would be great. If not, then we still have a chance to come back home and close it out."
LaMarcus Aldridge scored 19 points and Outlaw had 14 for the Blazers.
Yao went 7-for-14 from the field, his best game since he scored 24 in Game 1, a 108-81 Rockets victory.
Roy and Yao both shot well in the first half after both defenses keyed on them in Game 3. Roy scored 15 points and went 6-for-6 from the free-throw line, while Yao went 3-for-6 from the field and had 11 points.
Houston's offense went stagnant after Scola's layup put the Rockets up 58-51 with 6:43 left in the third quarter. Roy continued to draw Houston's defense with aggressive drives and either drew contact or found teammates for open shots.
"I tried to change my approach from Game 3," said Roy, who went 8-for-17 from the field and hit two 3-pointers. "I just tried to take what they gave me."
Aldridge scored six points and Steve Blake sank a 3-pointer during the Blazers' 19-6 run. Roy scored 10 in the third quarter, going 6-for-6 from the free-throw line.
The Blazers had a perfect night from the free-throw line in a playoff game for the first time since June 14, 1992, when they set an NBA finals record by going 21-for-21 in a Game 6 loss to Chicago.
The Rockets missed their last seven shots of the third quarter to fall behind, but Yao dunked and Von Wafer sank a 3-pointer to get Houston going again.
Notes: Portland, in the postseason for the first time since 2003, has lost 10 of their last 11 road playoff games. ... The Rockets are 34-4 this season when Yao scores at least 20 points. ... The Rockets grabbed 10 offensive rebounds in the fourth quarter to generate 13 second-chance points.