PORTLAND — The San Antonio Spurs are not letting up now that they’ve secured a place in the playoffs. There’s too much scrambling in the Western Conference.

Tim Duncan had 27 points and 11 rebounds and San Antonio beat Portland 72-65 on Sunday, extending the Spurs’ winning streak over the Trail Blazers to 12 straight games.

“It’s tough because every game really, really counts. At this point of the season usually you get to rest a little more, and relax a little more,” Duncan said. But now, every game is a big game.”

San Antonio is among a handful of teams who can bump New Orleans out of the top spot in the West. With the win against Portland, the Spurs moved within 11⁄2 games of the Hornets.

Manu Ginobili’s dunk with 1:31 left all but sealed it for the Spurs, who handed the Blazers their fifth consecutive loss. Ginobili finished with 10 points and six assists.

The Spurs were coming off a 90-64 loss at Utah on Friday that snapped an eight-game winning streak. But the defending NBA champions clinched a playoff spot on Saturday when the Sacramento Kings beat the Denver Nuggets 118-115.

San Antonio’s Tony Parker hit consecutive baskets, a running jumper and a jumper from the top of the key, to make it 70-60 with 3:37 left in the game.

“In past seasons with five games to go, you knew you could be first, second, third or even fourth, and that’s it. This year it could be seventh, so it puts pressure on everybody,” Ginobili said. “We can’t slow down, we have to keep playing.”

All-Star guard Brandon Roy, who returned after a four-game absence because of a groin injury, led the Blazers (38-39) with 18 points. Travis Outlaw added 14 and LaMarcus Aldridge had 12 points and 11 rebounds.

Portland, eliminated from playoff contention last week, was coming off a 95-86 loss to Houston on Thursday. With five games left, the Trail Blazers hope to finish with a winning record.

“Of course winning is the goal to finish out the season. We want to win every game,” Aldridge said. “We wanted to win tonight but the ball didn’t bounce our way.”

The Blazers were without starter Martell Webster, who suited up for Thursday night’s game but experienced dizziness and flu-like symptoms and was taken to a hospital. Webster spent the night when doctors found an irregular heartbeat and he was not at Sunday’s game.

The Blazers also lost center Joel Przybilla, who broke a bone in his right hand during the second quarter Sunday night and will miss the final five games of the season.

Przybilla was trying to block a shot when his hand hit the rim hard. The 7-foot-1 starter was averaging 4.8 points and 8.4 rebounds a game. Since the All-Star break, he had been averaging 11.4 rebounds.

Przybilla is one of just three Blazers who have played in all 77 games so far in the season.

“That’s a sad situation. Joel has played well all year long,” Portland coach Nate McMillan. “I know that one of Joel’s goals was to play all 82 games, and to have a freak deal like that happen is really too bad.”

“This is all the more unfortunate because Joel had his mind set to play all 82 games this season, and he almost made it happen,” general manager Kevin Pritchard said. “When you look at what he’s accomplished, Joel put his heart and soul into this season, and he gave us his all every night.”

Przybilla had a career-high 26 rebounds on March 22 against the Los Angeles Clippers, tying the franchise record for a regulation game and coming one short of the overall record.

The fourth-year Blazer also had 93 blocked shots this season.

“He went up and broke it, that’s crazy,” Aldridge said. “That’s bad luck there.”

Both teams got off to a sluggish start Sunday. The Blazers made just five of 22 field goals (22.7 percent) in the first quarter. The Spurs were just 6-of-17 (35.5 percent), and held a 17-13 lead.

Notes: Webster was expected to be examined by the Blazers’ cardiologist early this week. ... The Blazers are 1-7 this season without Roy.