AP Sports Writer
OKLAHOMA CITY (AP) -- James Harden is going to need much more help from his Houston Rockets teammates if he hopes to knock off the team that traded him away before the season started.
Kevin Durant scored 24 points, Russell Westbrook made a run at a triple-double in three quarters and the Oklahoma City Thunder routed Harden and the Rockets 120-91 on Sunday night in Game 1 of their first-round playoff series.
"Believe it or not, I think this was good for us," Harden said. "Losing like this was definitely good for us. Now we know how to play."
Harden scored 20 but Houston was held 15 points below its regular-season average while shooting 36 percent. The Rockets, who set a franchise record for 3-pointers during the regular season, finished 8 for 36 (22 percent) from behind the arc.
Harden didn't get much help from the rest of his fellow starters, who combined for a total of three career playoff starts, all by center Omer Asik. None of the other starters scored in double figures and the unit went 17 for 50 from the field, with Harden making just six of his 19 attempts.
"We really don't have an excuse anymore," said Jeremy Lin, one of three Houston starters making their first career playoff appearance. "We've gotten it out and played terrible all the way across the board -- offensively, defensively. That one's over with."
The Rockets made the playoffs for the first time in four years after acquiring Harden in a surprising trade at the end of training camp. He went on to become an All-Star and finish fifth in the league in scoring.
"James, on this team, has to shoulder a ton of responsibilities for us and he's been great all year long," coach Kevin McHale said. "He's had an all-pro type of year. ... He'll play better, just like everybody.
"We ask him to do an awful lot for us -- handle the ball, score the ball, pass the ball, make plays. I think that he had it going there for a little bit, but it wasn't James. It was us in general as a team. We never really caught a flow at all tonight."
Game 2 is Wednesday night in Oklahoma City.
Harden said he tried to block out what kind of reaction he might get from the crowd that once cheered for him and wore fake beards to mimic his trademark look. He was just focused on trying to win.
Hours before going head-to-head with Harden, Durant said that "we're not looking at him as a friend right now." But even right before tipoff, the situation didn't seem natural.
"It felt a little awkward just looking across there during the national anthem and seeing him with another team, but we've got to get past that. We're competing against his team, and he wants to win so bad," Durant said afterward. "We know him personally, so we know how hard he competes and he knows how hard we compete."
After letting Houston wipe away an 11-point deficit in the first half, the Thunder regained control with a 14-1 surge just before halftime and kept pouring it on.
Just after a fan nailed a half-court shot to win $20,000 in the break after the third quarter, Durant drove for a two-handed slam while getting fouled and Oklahoma City was soon up by 30.
Harden said he thought his team was "shell shocked" with so many players making their playoff debut, and they played like it.
"We didn't have a rhythm as a team. I felt like it was basically one on five every time," Harden said.
McHale said he thought players were jogging, instead of going at their usual fast pace, and then failed to string together passes on offense.
"We just want to try to make them uncomfortable every time down," Durant said.
The Thunder were already up by 23 when Larry Hill connected on the half-court shot and went bounding toward Oklahoma City's huddle in celebration, getting congratulated by Thabo Sefolosha before the team's bison mascot pulled him back away.
Durant's dunk sparked a string of seven straight points for Oklahoma City, and Harden never even came off the bench in the fourth quarter. Coach Scott Brooks called timeout and pulled Durant a few moments later, and reserves finished out the game for the Thunder.
Russell Westbrook ended up with 19 points, 10 assists and eight rebounds. Serge Ibaka chipped in 17 points and Kevin Martin, Harden's replacement in the sixth man role, had nine of his 16 points in the fourth quarter with the game already in hand.