LaMarcus Aldridge had 30 points and eight rebounds and Portland clamped down on Oklahoma City in the second half to knock the Thunder from the top spot in the West with a 103-93 victory on Tuesday night.
The Blazers are the only team in the West without two losses this season.
"We've got a lot of players that can do a lot of different things," said Wesley Matthews, who added 16 points.
"You can't replace Brandon Roy, with all of the things that he did for this organization and the community itself. But we've got a lot of guys that can play and are willing to."
Gerald Wallace contributed 13 points and 10 rebounds for Portland, which held Oklahoma City to 34 percent shooting in the second half to push ahead on an off night for All-Stars Kevin Durant and Russell Westbrook.
The Thunder were held to only 40 points on 13-for-38 shooting in the second half after making 51 percent of their shots and leading most of the first half.
"That's good. That's the way we're capable of playing," said Raymond Felton, who had 12 points, seven assists and only one turnover.
"I feel like if we play like that every night, or at least try to, we'll have a good season."
James Harden made his sixth career start in place of Thabo Sefolosha (flu-like symptoms) and led the way for the Thunder with 23 points. Westbrook had 22 points on 8-for-18 shooting and Durant finished with 19 points while hitting 8 of 26 shots.
Oklahoma City started the season 5-0 before losing for the second straight night.
"I think sometimes you need losses to remind you that you've got to get better," Nick Collison said. "You wish it wasn't like that. You wish you could always realize the need to improve but human nature, sometimes you get a little lax when you're winning."
Neither team led by more than seven until the fourth quarter, when Portland started to inch away.
Nicolas Batum and Felton hit 3-pointers on consecutive possessions, and Batum added another from the right wing just before the shot clock expired to bump the Blazers' advantage up to 92-82 with 5:55 remaining.
Wallace countered a couple easy buckets by Westbrook by backing in against Durant for a pair of layups, and Aldridge's 19-footer from the top of the key put Portland up 98-86 with 2:46 to play.
Thunder coach Scott Brooks called a timeout but his team couldn't mount a rally. Felton all but sealed it when he missed a layup with 45 seconds left but came out with the offensive rebound and hit two foul shots to make it 100-91.
"It just tells us one thing -- that we have to get better," Oklahoma City coach Scott Brooks said. "We have to keep improving, but our guys understand that. They understand that this is not the final product that you will see."
Aldridge and Oklahoma City's Kendrick Perkins were both called for technical fouls after Perkins slammed his shoulder into Aldridge following a rebound. The two were quickly separated by teammates before the conflict escalated.
Portland, which also already won at Denver, also grabbed an early advantage in the Northwest Division race.
"You want to win every division game you can," Matthews said. "No matter how early it is, it's a good win."
The Thunder led for most of the first half, when their shots were falling -- except for Durant's. Collison had back-to-back layups to finish the first quarter, and Harden's 3-pointer from the right wing in the opening minutes of the second quarter gave Oklahoma City its largest lead of the game at 32-25.
Aldridge went to work bringing the Trail Blazers back, scoring eight points after the midway point of the second quarter to cut the deficit down to 53-51 by halftime.
He also had a two-handed slam off of a Marcus Camby alley-oop and also had a right-handed dunk during a 13-4 run that gave Portland a 74-67 lead in the final 3 minutes of the third quarter. The Blazers wouldn't trail again.
Matthews said that Aldridge told the team at halftime that the game was like the high-scoring Rose Bowl between Oregon and Wisconsin.
"The first team to play defense was going to win the game. It might as well have been us," Matthews said.
Durant made only three of his first 11 shots and it never really got better. After he hit consecutive shots to end the first half, he went 3 for 13 in the second half. Westbrook was 5 for 15 before making his last three attempts of the game.
"I'm a scorer, so I can't get down on one game," said Durant, the two-time scoring champion. "I can't let it snowball to the next."
Collison said the Thunder, who set out this season trying to improve on their assist numbers despite being one of the league's highest-scoring teams last season, need to move the ball and play better together.
"It seems like we're 40 feet from the basket trying to create something a lot," he said. "Our overall offense needs to get better."
Durant was named the Western Conference player of the week for the first week of the season, averaging 27.4 points as the Thunder started the season 5-0. ... Portland had a 46-40 edge on the boards and has outrebounded all five of its opponents this season. The Blazers had only nine turnovers after committing 46 in their previous two games. ... Oklahoma City had been 20-6 after losses last season, but lost in its first bounce back game this season.
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