The Oklahoma City Thunder secured a spot in the NBA playoffs on Sunday with a testing 99-90 win over division rivals Portland.

The Thunder went on a decisive 17-8 run over the final 6:18 of the fourth quarter led by Russell Westbrook, who scored 11 of his 28 points in the blitz.

"Both teams really played as hard as they can play," Thunder coach Scott Brooks said, "fighting through every possession."

They also came up with a key defensive stand in the last minute when Kendrick Perkins blocked a shot by Gerald Wallace and Serge Ibaka blocked Andre Miller to preserve a four-point lead. Westbrook completed the sequence with a layup to stretch the advantage to six.

Kevin Durant struggled in the second half, going 0-for-8 from the field, but scored 21 points for the Thunder and had five blocked shots. Ibaka added 18 points.

"There was a time a few years back that if Kevin goes 0-for-8, there's a good chance that we don't win this game," said Brooks. "Guys have to step up. There's always going to be a different guy."

Portland was unable to capitalize on Wallace's sizzling 40-point performance, with LaMarcus Aldridge the only other Trail Blazer to reach double digits with 20 points.

"It wasn't enough," said Wallace. "I'd rather take the win than take the points."

In Memphis, Tennessee, the Grizzlies strengthened their grip on an NBA playoff spot with a 111-104 win over the San Antonio Spurs in what could be a precursor to a possible postseason matchup.

Tony Allen and Zach Randolph had 23 points apiece for Memphis, which currently holds the eighth and final playoff spot in the Western Conference. If the Grizzlies earn the No. 8 seed, they will likely face the NBA-leading Spurs in the opening round of the playoffs.

George Hill matched his career high with 30 points.

Comfortable win

In Los Angeles, Los Angeles inched closer to the top of the overall NBA standings with a comfortable 102-84 win over New Orleans. Kobe Bryant scored 30 points and Pau Gasol had 23 points and 16 rebounds as the Lakers made it 15 wins from 16 games.

The two-time defending NBA champions jumped to an 18-point lead in the first half and weathered the Hornets' fourth-quarter rally to sweep the four-game season series with a possible first-round playoff opponent.

In Miami, three Miami players reached 30 points and 10 rebounds as the Heat downed Houston 125-119.

LeBron James had 33 points and 10 rebounds, Chris Bosh added 31 points and 12 rebounds, and Dwyane Wade shook off a bruised tailbone to finish with 30 points and 11 boards as Miami made it eight wins in nine games.

Elsewhere, it was: Mavericks 91, Suns 83; Celtics 85, Timberwolves 82; Kings 114, 76ers 111, OT; Hawks 99, Cavaliers 83; and Warriors 114, Wizards 104.