Golden State closed to 92-88 when Curry went 1 for 2 at the line, but Duncan threw in a running hook and a 16-foot jumper to give San Antonio an eight-point lead with 2:37 remaining.
"My jump shot's coming back," Duncan said. "It doesn't feel great, but it's going in a little bit, so I'll take it. Everything else feels really good. I feel healthy, moving well. (My) body feels good and shots are going in."
Duncan was 11 for 17 from the field and 3 for 3 at the line. It was his 13th game of at least 20 points and 10 rebounds this season.
"Timmy has his rhythm back," Spurs coach Gregg Popovich said. "He's in great shape and down the stretch we went through him. Manu and Timmy really decided to do that on their won and they did a great job of it."
The Spurs needed Duncan to step up with All-Star point guard Tony Parker (sprained left ankle) still about a week away from rejoining the team, and the 16-year veteran is averaging 27.7 points, 14.7 rebounds and 3.3 rebounds in his last three games -- all home victories.
"Unbelievable; he's just unbelievable," Splitter said. "He's just figuring out how to play great at his age. It's not easy, he's not same guy like 10 years ago. He doesn't have the same quickness, but he still knows how to play this game."
Duncan also set the tone defensively.
Golden State (first) and San Antonio (fourth) are among the top five in 3-point percentage, but neither team connected from long range until Ginobili knocked down his second attempt with 10:30 left in the first half.
It was part of a greater emphasis on defense by the Spurs, who struggled in a 119-116 victory against Cleveland on Saturday.
"Focus more than anything," Duncan said. "We've been playing hard. We just kind of get out of whack every once in a while kind of as the season goes along. It's a long season. People lose focus for a little while. It's good to go through a stretch like that to get a team refocused; to get guys individually refocused. I think we've done that."
San Antonio still had some defensive lapses. Golden State went on a 10-1 run after De Colo's 17-foot jumper gave the Spurs a 91-78 lead with 8 minutes remaining. But that's when Duncan had his late run.
"Tim made plays and that is what he does," Curry said. "We got back into it and had a chance to win at the end. If I would have made that second to last 3 I took, that would have changed the game."
Curry missed a 3 pointer with 3 minutes left and Duncan followed with his 16-foot jumper that gave San Antonio a 96-88 lead.
San Antonio outscored Golden State 38-25 in the second quarter, going 6 for 11 on 3s after missing all four attempts in the opening period. Matt Bonner and Danny Green hit back-to-back 3s late in the second quarter as San Antonio led 60-47 at halftime.
De Colo had one of the highlights in the first half when he stripped Jack at midcourt and sprinted to the basket for a dunk, prompting Duncan to leap from his seat and shout "atta boy."
"I thought he was a really physical player tonight," Popovich said. "He showed a penchant to stick his nose in and played physically. He was very good in that regard and that's what we've been wanting to see from him.
"He's a smart player, we already know that, but he's got to be able to bang and hit and keep up with a physical game like it was tonight -the way it's going to be in the playoffs."
Parker participated fully in San Antonio's practice Tuesday, but Popovich said he was still about a week away from rejoining the team. ... All but three of San Antonio's 14 remaining games are against teams with a winning record. ... Warriors F Richard Jefferson, who played two seasons with the Spurs, was booed when he entered the game late in the first quarter. ... Duncan was assessed a technical foul with 6:59 left for arguing a foul called against De Colo. It was Duncan's first technical foul since April 15, 2007, against the Dallas Mavericks.
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Around The Association
MVP: It's Tim Duncan in a no-contest. The Big Fundamental put up 25 points, 13 rebounds, six assists and four blocked shots as he wreaked havoc on the Warriors' interior.
X factor: As Gregg Popovich has toyed with the backup point guard position, especially with Tony Parker out, Nando De Colo stepped up with 10 points on 5-of-6 shooting and just one turnover, while doing a solid job defensively against the Warrior guards.
Defining moment:Just when a Stephen Curry 3-pointer with 1:48 left seemed to give the Warriors hope they could mount a late comeback, back-to-back 3s from Manu Ginobili and Kawhi Leonard put Golden State to bed.