Spaniard Serge Ibaka was running at full steam as he aggressively defended the San Antonio Spur's Tony Parker.

But even his 6-foot-10 frame could not stop Parker from swishing a buzzer-beater as the Oklahoma City Thunder fell to the Spurs 86-84.

Parker sank a 21-footer as time expired as the Spurs won a thrilling rematch of the Western Conference finals on Thursday night.

Throw in the trade that sent one of the Thunder's key players, James Harden, to Houston, and that's two stunners for the team during the first week of this NBA season.

Parker scored the last of his 14 points while Ibaka — the NBA's leading shot-blocker last season —tried his best to defend him. 

"I was like, I have to shoot fast," Parker said about eluding the outstretched arm of Ibaka. "He was coming very fast." 

But when the All-Star guard calmly swished a long jumper from the left wing, Parker could do nothing but break into a sustained scream while his teammates mobbed him in front of the Thunder bench.

Thunder star Kevin Durant led all scorers with 23 points and began his sixth NBA season by becoming the second-youngest player behind LeBron James to reach 10,000 career points. Durant, however, stood silent under the basket for several seconds after Parker's shot before walking off the court.

"We lost him. We didn't get him in time, but he still made a tough shot over Serge," Thunder coach Scott Brooks said. "It's not an easy hand to shoot over."

The defending West champions broke up their Big Three by trading the NBA's Sixth Man of the Year to Houston on Saturday. Harden had 37 points and 12 assists in a brilliant debut with the Rockets on Wednesday night.

Speaking before the season opener, Brooks succinctly acknowledged Harden's performance before saying his team was moving forward.

Until Parker's game-winner, it was almost as if nothing had changed for Oklahoma City.

Tim Duncan led the Spurs with 20 points and eight rebounds. Parker also had 11 assists and hit a 3-pointer with 28.4 seconds left that tied the game at 84 and set up his buzzer-beater on the next possession.

Durant also had 14 rebounds. Russell Westbrook scored 18 points but made a poor pass on the Thunder's final possession that gave the ball back to the Spurs with 5.9 seconds left, giving Parker plenty of time to set and release his shot.

The Thunder are starting anew with newcomers Kevin Martin and Jeremy Lamb, who along with draft picks, are what the Thunder got in exchange for their third-leading scorer. Small-market Oklahoma City wasn't willing to offer Harden a maximum contract, and the No. 3 overall pick in the 2009 draft wouldn't accept its lesser offer.

By Wednesday, Harden had agreed to a five-year, $80 million extension with the Rockets. That night, he stepped into Houston's starting lineup and became the first player in NBA history to have more than 30 points and 12 assists in a debut with a new team.

Asked before Thursday's game whether the second-guessing had begun, Brooks didn't linger on the topic.

"He's played good basketball. He had a good game," Brooks said. "We're real focused on our group, our guys and moving forward."

Westbrook, who took responsibility for losing Parker on the screen on the game's final play, acknowledged the first game without Harden didn't feel the same.

"It was definitely odd not playing and practicing with him," Westbrook said. "But we still need to find a way to win."

Martin had 15 points and was Oklahoma City's only bench player in double figures. But backup Eric Maynor made his own big contribution, hitting a half-court heave to tie the game at the end of the third quarter.

Spurs guard Manu Ginobili missed his second game with back problems but could make his season debut Saturday against Utah.

Parker played 35 minutes and scored 23 points in Wednesday night's season-opening win at New Orleans. He played another 35 minutes against the Thunder, more than what Spurs coach Gregg Popovich would prefer for his Big Three on back-to-back nights this early in the season.

"Down the stretch, you think he might be getting a little tired on the back-to-back," Popovich said. "Be he had his legs on the shot and did a great job."

Based on reporting by the Associated Press.

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