SAN ANTONIO, March 23 (Ticker) -- The Miami Heat climbed all the way into the playoff hunt only to hit the toughest part of their schedule.

Tim Duncan had 23 points and 11 rebounds and rookie Tony Parker added 14 points and eight assists as the San Antonio Spurs extended their season-high winning streak to 12 games with an 89-79 victory over the Heat.

Miami has rebounded from a sluggish start to pull within striking distance of the final Eastern Conference playoff spot. But the Heat's final 15 games feature matchups with nine playoff-bound clubs and started with a visit to the Alamodome, where they have lost 14 of 15 visits all-time.

The Spurs never trailed after scoring the game's first 10 points, highlighted by four points apiece from Parker and David Robinson. Miami pulled within 31-29 with 4:59 left in the second quarter, but San Antonio responded with a 13-4 run.

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Tony Parker played a very solid game, dishing out a game-high eight assists.
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"We got off to a bad start again and had to struggle to find a combination of energy out there," Miami coach Pat Riley said. "It wasn't until I went to the bench that our team showed enthusiasm."

Duncan scored five points during the spurt and the Spurs went into halftime with a 44-36 advantage.

The Heat climbed within 55-52 early in the third quarter, but San Antonio again responded, this time with a 16-6 run to regain control.

Duncan scored seven points and Parker six during the stretch, which gave San Antonio a 71-58 cushion heading into the final period.

"We did a good job grinding out a win," Spurs coach Gregg Popovich said. "We played 48 minutes against a team that is the best in the league at grinding games out. They're one of the best defensive teams in the league and our guys rose to the occasion."

Charles Smith scored 12 points and Robinson added 11 and 10 rebounds for the Spurs, who are the midst of their longest winning streak since a franchise-record 17-game tear from February 29-March 31, 1996.

"We got a good streak going here and we had a good game tonight," Duncan said. "We know that (the Heat) are a team that plays 48 minutes. This is a great time for us, we're playing well."

Jim Jackson scored 17 points and Alonzo Mourning collected 16 and 11 rebounds as Miami fell four games behind Indiana and Charlotte for eighth place in the East.

The Heat shot just 42 percent (31-of-74), including 2-of-10 from 3-point range, and committed 18 turnovers leading to 27 points for the Spurs.