Damian Lillard scored 30 points and the third-seeded Portland Trail Blazers opened their playoff series against the No. 6 Oklahoma City Thunder with a 104-99 victory on Sunday.

Enes Kanter added 20 points and a career playoff-high 18 rebounds for the Blazers, who were making their sixth straight postseason appearance. CJ McCollum added 24 points.

Russell Westbrook had 24 points, 10 assists and 10 rebounds for his ninth career postseason triple-double. Paul George, who was a game-time decision because of a sore shoulder, added 26 points and 10 rebounds after a slow start.

Portland led by as many as 19 points in the first half, but the Thunder pulled within 80-77 early in the fourth quarter. Oklahoma City couldn't get closer and Lillard hit a 30-footer to extend the Blazers' lead to 89-81 with 6:38 left.

Westbrook appeared to hurt his right knee or ankle and grimaced while trying to walk it off. Trainers attended to him on the bench at the next timeout but he returned and his layup closed the gap to 91-87 with just under 4 minutes left.

Oklahoma City got within 93-92 on George's 3-pointer, but Lillard answered with another long 3 to keep the Blazers ahead. Al-Farouq Aminu made free throws with 2:09 left to extend Portland's lead to 98-92.

George made a 3-pointer with 8.2 seconds remaining to get the Thunder within 100-97 but Portland hung on. It was the first postseason meeting between the teams since the Thunder moved from Seattle to Oklahoma City. Oklahoma City beat the Blazers in all four meetings this season, including a heated 129-121 overtime victory on March 7.

The Thunder have been to the playoffs every season since moving from Seattle in 2008, but they haven't gotten past the opening round for the past two seasons.

George was nursing a sore right shoulder and was considered day-to-day for Sunday's game but he started. However, he was just 1 for 6 from the floor in the opening quarter. George missed the Thunder' regular-season finale Wednesday at Milwaukee because of the nagging injury, which also kept him out of games on Feb. 28, March 2 and March 3.

McCollum missed 10 games down the stretch with a left knee strain and had only played in two games since returning. But he started and hit his first two 3-point attempts.

The Blazers' hopes for postseason success were dealt a blow last month when center Jusuf Nurkic was lost for the season with a broken left leg. Nurkic was averaging 15.6 points and 10.4 rebounds when he sustained the gruesome injury during a game against the Brooklyn Nets.

Kanter, signed just before the All-Star break after he was waived by the New York Knick, has started in Nurkic's place.

Portland jumped out to a 26-15 lead early on McCollum's third 3-pointer. Portland went on to lead the opening quarter by as many as 17 points, paced by Lillard with 12 points. The Thunder did not make any of their six 3-point attempts, while Portland was 7 of 10.

Seth Curry made consecutive 3-pointers but the Thunder rallied in the final six minutes of the half to trail by just 54-48 at the break. But they still struggled from 3-point range, making just two of 18 attempts. George was 1 of 8 from the perimeter.

There was simmering tension between the teams. Terrance Ferguson and McCollum had a heated exchange in the second quarter, earning technical fouls. Ferguson earned his third foul and headed to the bench.

Westbrook's layup got the Thunder within 64-60, but he collected his fourth foul late in the third and went to the bench. The Blazers went into the fourth quarter with a 76-69 lead.

TIP-INS:

Thunder: While the Thunder swept the Blazers 4-0 during the regular season, Portland swept them in four games the season before.

Trail Blazers: Blazers coach Terry Stotts concluded his pregame talk with the media by saying. "All right. Masters." The Blazers were 8-8 in the postseason against the SuperSonics. ... Portland had won the last eight regular-season games at the Moda Center. ... Kanter had his third playoff double-double. ... The Blazers haven't made it out of the first round for the past two seasons. Last year as a No. 3 seed Portland got swept by the New Orleans Pelicans.

UP NEXT: Game 2 is Tuesday night at the Moda Center. 

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