The Rockets spurted to a 25-12 lead after the first quarter, and seemed comfortably ahead, before being out-scored, 34-27, in the fourth, which made the game interesting.
It is the first time Houston won its first three games since the 1996-97 season.
Portland's Brandon Roy had a game-high 23 points and five assists. LaMarcus Aldridge had 20 points and eight rebounds, and Martell Webster added 15 points and eight rebounds for the Trail Blazers, who lost for the third time in their season-opening three-game road trip.
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