The Oklahoma City Thunder rallied for a 103-97 victory on Saturday night to complete a first-round series sweep of the defending NBA champion Dallas Mavericks.

Harden scored 15 of his 29 points in the fourth quarter, including seven in a row and nine in the Thunder's 12-0 run after they trailed by 13 points with 9:44 left.

"I got into attack mode," Harden said. "I was determined to make plays."

Dallas became the second defending champion in five years to be swept in the first round. After beating the Mavericks in the 2006 NBA Finals, Miami lost in four games to Chicago the next year.

Kevin Durant had 24 points and 11 rebounds for the Thunder, who will play the winner of the series between the Los Angeles Lakers and the Denver Nuggets. 

Oklahoma City finished off the Mavs without starting center Kendrick Perkins, who left the game with 4:09 left in the first quarter with a right hip strain. He had two rebounds, two assists and missed his only shot in his 8 minutes.

Dirk Nowitzki led Dallas with 34 points, Jason Kidd had 16 points and eight assists, while Jason Terry added 11 points for the Mavericks.

Russell Westbrook and Derek Fisher had 12 points each for the Thunder.

Dallas led 86-73 on a 3-pointer by Terry before Harden scored seven in a row -- on a three-point play and two other baskets. Durant then made a 3-pointer, and after Nowitzki was short on a 14-footer, Harden drove for a powerful two-handed slam that got the Thunder within 86-85.

The game was tied at halftime before Nowitzki had 12 points and Kidd made three 3-pointers in the third quarter, when the Mavs scored 34 points to take an 81-68 lead.

Dallas had never been swept in a best-of-seven series. And the Mavericks hadn't lost four playoff games in a row since the 2006 NBA Finals against the Heat, when they took a 2-0 series lead before losing the rest.

The Thunder outscored the Mavericks 35-16 in the fourth quarter to close the series.

(Photo by Ronald Martinez/Getty Images)