San Antonio continue to run roughshod across the NBA, completing their second-straight four-game series sweep in the postseason by beating the Los Angeles Clippers 102-99 in game four. Tim Duncan had a team-high 21 points and nine rebounds and Tony Parker finished with 17 points and five assists for the Spurs who have won 18 consecutive games dating back to the regular season. The top-seeded Spurs will now face either the Oklahoma City Thunder or the Los Angeles Lakers in the Western Conference final, beginning in San Antonio. "We got it done through perseverance," Duncan said. "We stuck with it. We kept moving the ball and believing in what we were doing. "It is great to have a close game like this. It is a good experience for our young guys." San Antonio's last defeat was to the Lakers on April 11 and their 8-0 record in the playoffs includes a sweep of the Utah Jazz in the opening round. Guard Parker said the Spurs are only halfway to their goal. "It doesn't mean anything," said Parker. "We haven't accomplished anything. We will see who we play in the next round." Guard Chris Paul led the Clippers with 23 points and helped keep the game close down the stretch. But Paul also had a key turnover in the final minute and then had a chance to tie it with a jumper with four seconds remaining but his shot from in close hit the rim and bounced out of harm's way. "We just didn't execute. That's my fault," Paul said. "The first one I turned it over and the second one I missed the shot. "It is disappointing for me to not being able to come through for my team. We know we lost to a good team. I am happy we never gave up." Blake Griffin had 21 points and DeAndre Jordan finished with 10 points and eight rebounds for the Clippers who were trying to achieve the improbable. No NBA team had ever come back from a 3-0 deficit to win a series. As if he didn't already have enough to worry about with a sore left hip and a sprained right knee, Griffin was sent to the dressing room for repairs just before the half after he cut open his lip in a collision with Spurs' Manu Ginobili. He received four stitches. San Antonio took two of three from the Clippers during the regular season in 2011-12. Game four capped a marathon sports weekend for Los Angeles and the downtown Staples Center arena. The arena, also home to the Los Angeles Lakers and the National Hockey League's Kings, hosted six playoff games in four days. The country's largest cycling race, the Tour of California, also wrapped up Sunday outside Staples Center adding to the festivities.