PORTLAND, Oregon: Portland's Damian Lillard hit a 3-pointer at the buzzer to give the Trail Blazers a stunning 99-98 win over Houston on Friday, clinching a 4-2 win in their playoff series and a place in the NBA Western Conference semifinals for the first time 14 years.

On a dramatic day in the playoffs, Dallas staged a fourth-quarter comeback to overrun Texan rival San Antonio and square their series at 3-3, while Brooklyn also won at home against Toronto to force a Game 7 in their series.

Portland, making its first playoff appearance since 2011, had been eliminated in the first round in its last six trips, and had not advanced to the second round since 2000.

Dwight Howard's layup and foul shot put the Rockets up 96-94 but Nicolas Batum's fadeaway jump shot tied it again with 39.9 seconds left.

Chandler Parsons scored on a reverse layup with 0.9 seconds left to give Houston the lead but there was just enough time for Lillard to hit a 3 that will go down in Blazers folklore.

Portland will face the winner of the series between San Antonio and Dallas, and that remains up for grabs after the Mavericks pulled off an equally dramatic 113-111 comeback win over the Spurs.

Monta Ellis scored 12 of his 29 points to lead a fourth-quarter surge. It was an unlikely comeback by the eighth-seeded Mavericks, as San Antonio had won every time this season when leading after three quarters in a road game.

Dirk Nowitzki added 22 for Dallas, who will travel to San Antonio for the decider on Sunday with the knowledge that the last time they went there for a Game 7 they won, in 2006.

Tony Parker scored 22 to lead the heavily favored Spurs, who won all four games against Dallas during the regular season and had been expected to quickly dispatch their state rival.

Brooklyn had a relatively comfortable 97-83 home win over Toronto, with Deron Williams shaking off a second-half injury to score 23 points.

Despite appearing to hurt his left foot or ankle early in the third quarter, Williams dominated his matchup with Kyle Lowry and helped the Nets put it away with a 3-pointer with 1:13 left that made it 92-79.

Game 7 is Sunday in Toronto, with the winner advancing to face defending champion Miami.

DeMar DeRozan scored 28 for the Raptors, who have never won a postseason series that went seven games, and have not won any playoff series for 13 years.

Sterling breaks silence, Stiviano talks about scandal

Meantime, Donald Sterling, the embattled owner of the Los Angeles Clippers banned for life by the NBA after making racist comments, has broken his silence about the scandal.

Online magazine duJour reported Friday that Sterling said, "I wish I had just paid her off," referring to his girlfriend, identified only as V. Stiviano.

The 80-year-old billionaire was caught speaking with Stiviano and making racist comments on a recording made public last weekend.

The recording touched off a firestorm that led NBA commissioner Adam Silver to banish Sterling from the league for life.

On the recording, Sterling said he did not want Stiviano -- who describes herself as the magnate's "personal assistant" -- to bring black people to his game, and asked her not to post pictures of herself with African Americans on social media websites.

Stiviano spoke to the ABC News program "20/20" late Friday, saying she thought Sterling should apologize but whether or not he would, "Only God knows."

"I think he feels very alone, not truly supported by those around him. Tormented, emotionally traumatized," Stiviano said of Sterling.

She denied being Sterling's "mistress" and said that she loved him "like a father figure."

"I'm with him in a state where I want to help him, urging him to come to his own rescue."

"I think Mr. Sterling is from a different generation than I am," she told ABC.

"I think he was brought up to believe these things ... segregation, whites and blacks."

But according to Stiviano, "through his actions he's shown that he's not a racist. He's shown to be a very generous and kind man."

Stiviano also said that there were "a number of other hours" of recordings "that the world doesn't know."

In March Sterling's wife Rochelle sued Stiviano, claiming that she has received millions of dollars in gifts from the billionaire that need to be returned.

Separately, ESPN and the New York Post reported that Sterling has prostate cancer.