HOUSTON — The Houston Rockets are one win away from finally escaping the first round.

Yao Ming 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.

Brandon Roy scored 31 points and went 13-for-13 from the free-throw line for the Blazers.

Portland led 70-64 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.

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 lost in Houston for the 12th time in their last 13 visits.

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. Portland centers Joel Przybilla and Greg Oden each picked up two early fouls trying to guard Yao in Game 4, forcing Blazers coach Nate McMillan to go to a smaller lineup.

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.

The Rockets outrebounded Portland 20-16 in the half and led 50-44 at the break.

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.

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 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. Scola's jumper from the free-throw line tied it at 77-all, and Yao's hook shot on Houston's next trip put the Rockets back in front.

The lead changed hands three times before Battier's 3-pointer from the corner with 3:25 left gave the Rockets an 85-83 lead. Carl Landry hit a jumper from the free-throw line before Aldridge's free throws with 2:15 left trimmed Houston's lead to 87-85