Duncan was scratched a half-hour before tip-off Tuesday night because of a sore right knee, and Spurs coach Gregg Popovich said after the game he didn't know the severity of the injury. Popovich said Duncan would be evaluated by doctors Wednesday morning, putting his status for this game in doubt.

The coach also said his All-Star forward appeared fine Tuesday morning but was stiff and had trouble getting loose while warming up. Duncan, who was walking around the locker room before Tuesday's contest, was not on the bench during the game.

"It was strange," Popovich said. "He was good this morning, but this evening he couldn't move on it."

The Southwest Division-leading Spurs (38-17) were already without Manu Ginobili, who hasn't played since the All-Star break because of a stress reaction in his right ankle and is expected to miss at least two more weeks.

Tony Parker - the only healthy member of the trio that has led San Antonio to three championships in six years - stepped up Tuesday, scoring 37 points with a season-high 12 assists in a 93-76 win over Dallas.

"I love those opportunities," said Parker, whose point total was the third-highest of his eight-season career. "I'm not going to say I want to play every game like that, but you can show what you can do."

The Spurs' fifth straight home win came in their first game in San Antonio since Jan. 31. They'd played their previous eight games on the road while the AT&T Center was occupied by the annual San Antonio Stock Show and Rodeo.

The Spurs hope to continue their strong play at home by extending their dominance of the Blazers. Since a 95-76 loss Nov. 9, 2002, they've won 10 straight home games against Portland by an average of 15.7 points.

Portland (35-21) has already snapped one losing streak against San Antonio this season. It had dropped 12 straight overall in the series before taking a 100-99 home victory Oct. 31.

The Blazers, though, continue to struggle on the road, where they've dropped four straight. They nearly overcame an 17-point second-half deficit Tuesday night, but the rally fell short in a 98-94 loss in Houston.

"We need to learn to have the same intensity and focus and learn how to play for 48 minutes on the road," said Blazers coach Nate McMillan, whose team has one of the league's best home records at 23-5 but is 12-16 outside Portland. "We dug too big of a hole and we couldn't get out."

Blazers All-Star guard Brandon Roy, averaging 26.4 points and shooting 56.5 percent over his last five games, had 26 points, five rebounds and seven assists while shooting 10-for-18 in Portland's October victory over San Antonio.

Parker had 24 points and 11 assists in that game.