Yao Ming added 27 points and 12 rebounds for the Rockets, who won their fifth straight road game.

Portland, which trailed by as many as 25 points, has lost seven of nine. Rookie Brandon Roy led the Blazers with 20 points.

Houston Rockets guard Tracy McGrady, right, and Portland Trail Blazers guard Brandon Roy reach for a loose ball during the second half of an NBA basketball game in Portland, Ore., Wednesday, April 11, 2007. McGrady led the Rockets with 32 points as Houston won 99-95. [AP]

Roy fell on McGrady's legs with 58.8 seconds left. After spending some time on the floor, McGrady rose and walked gingerly on the sidelines. He was standing with his teammates as the clock wound down.

With his left knee wrapped in ice after the game, McGrady said he was not seriously injured.

"It's a little sore, nothing's torn," McGrady said. "I'm sure I'll feel better, it's nothing to worry about."

The Blazers made it interesting for the fans who were left at the Rose Garden when Travis Outlaw hit a 3-pointer with 12.8 seconds to go that narrowed the deficit to 94-91.

Rafter Alston made a pair of free throws for Houston before Jamaal Magloire narrowed it again with a dunk. Alston answered with one of two free throws, then Dan Dickau's reverse layup for Portland made it 97-95.

Yao hit a pair from the line with 0.1 seconds left for the final margin.

The Rockets continue to tussle with Utah for the fourth spot in the Western Conference and home-court advantage in the playoffs. The Jazz lost 115-106 to the Denver Nuggets on Wednesday night.

The Rockets will finish without Bonzi Wells, a former Blazer who on Wednesday was declared inactive for the rest of the season after skipping Monday night's 95-90 victory at Seattle. Wells left a message with the team's trainer saying he was concerned he was disrupting the chemistry of the team.

Wells averaged 7.8 points and 4.3 rebounds in 28 games, and was hampered this season by back and foot injuries.

Before the game the Blazers announced they would be without starting forward Ime Udoka for the rest of the season because of a knee injury. He was averaging 8.4 points and 3.7 rebounds.

The Blazers had just 10 players available for the game. Rookie forward LaMarcus Aldridge was diagnosed last week with Wolff-Parkinson-White Syndrome, a heart condition that is not considered career-threatening.

Earlier the Blazers lost top scorer and rebounder Zach Randolph (right hand) and center Joel Przybilla (left knee) for the season.

The Rockets jumped out to a 20-10 lead and went up by as many as 14 points in the first quarter, but the Blazers came back with consecutive baskets from Fred Jones, closing to 30-24.

But Houston took back control, and went up 43-28 on Shane Battier's 3-pointer. The Rockets led 53-36 at the half on Alston's 3-pointer.

Yao's turnaround jumper put Houston ahead 61-40 early in the second half.

Jones and Roy hit consecutive jumpers to narrow the deficit to 80-85 in the fourth quarter.

After Yao hit a pair of free throws, Jones scored a layup. McGrady answered with a 3-pointer that made it 90-82 and effectively snuffed the rally until Outlaw's 3-pointer.

It was the seventh time in franchise history and the second time in the past three seasons that the Rockets have reached 50 wins. Houston has three regular-season games left.