MEMPHIS, Tenn. – Tim Duncan wore a green flannel shirt, non-designer jeans and high-top sneakers while sitting atop a lime exercise ball after the San Antonio Spurs' victory late Saturday. At 37, Tim Duncan is old by NBA standards. On the court, however, he looks anything but.

Duncan scored seven of his 24 points in overtime while adding 10 rebounds, five assists and two blocks to spark the Spurs to a 104-93 victory over the Memphis Grizzlies in Game 3 of the Western Conference finals. With the Spurs now owning a commanding 3-0 lead in the series, Duncan is one more victory away from reaching his fifth NBA Finals and first since 2007.

"I'm very focused on another opportunity to make it to another championship and trying to win," Duncan said. "I'm not worried about how old I am or whatever it may be.

"…We've been counted out for a bunch of years and we haven't been there in forever. It would mean a lot. We obviously have one more game to win to get to that point, but I'm excited about the opportunity to get there."

Duncan is one of just four players from the 1997 NBA draft who were on an NBA roster this season, joining Chauncey Billups, Tracy McGrady and Stephen Jackson, the latter two being teammates of Duncan's for part of this season. Among the other players from that draft, Brevin Knight is now the Grizzlies' TV analyst, Jacque Vaughn is head coach of the Orlando Magic, Bobby Jackson is an assistant coach with the Sacramento Kings and Tariq Abdul-Wahad coaches San Jose (Calif.) Wilcox High School varsity.

Given that Duncan has played in 1,180 regular-season games and 203 more in the playoffs – and that he spent much of his career getting hit in the paint – one would have expected his game to show a considerable decline as he approaches 40. Instead, he was an All-Star this season and was just named to the All-NBA first team as a center.

"The greatest power forward of all time," Billups said in a text to Yahoo! Sports. "Just goes to show that real basketball will prevail. Fundamentals, efficient, cerebral basketball are still the way to go."

Said Spurs All-Star guard Tony Parker: "He's playing unbelievable. I don't know if many people at his age have done that in NBA history."

Duncan's perseverance was evident Saturday. The Spurs trailed by as many as 18 points in the opening quarter, and coach Gregg Popovich was so disappointed with his team's start that he benched all of his starters – Duncan included – about seven minutes into the game. The Spurs kept fighting and eventually caught up enough to send the game into overtime where Duncan took over.

Duncan scored six OT points in the Spurs' 93-89 Game 2 victory. He opened Game 3's OT with a 19-foot jumper and a three-point play. He added a crunching screen on Grizzlies point guard Mike Conley and a nice no-look pass to Tiago Splitter that led to another basket.

"He was huge the other night in overtime and got it done for us, and he did it again tonight," Popovich said. "That's why he is considered as great as he is for [16] years. He's been unbelievable. He feels a responsibility to carry us in those kinds of times, and he did it again tonight."

In the process, Duncan also moved ahead of Wilt Chamberlain for second in NBA playoff career double-doubles with 144 and passed Jerry West for sixth all-time on the playoff scoring list. Duncan, who is happy out of the spotlight, wasn't moved by the accomplishments.

Asked if the two benchmarks meant much to him, Duncan said: "It means I never know [about them] until you tell me."

By 31, Duncan already had four NBA championships and three Finals Most Valuable Player trophies. Injuries helped chip away at the Spurs' consistency, and though they've reached the West finals three times since, they haven't made it back to the Finals since '07. The Grizzlies knocked out the top-seeded Spurs in the first round two years ago. Last year, the Spurs owned a 2-0 lead in the West finals before Oklahoma City won the next four games.

"I never felt anything was promised," Duncan said.

Said Parker: "Timmy is getting old and we got to get it done for him. I always joke [with] him that it would be nice to leave with a championship."

Duncan finds the constant reference to his age humorous, but he also has an appreciation for how hard it is to return to the Finals. If the Spurs can get one more victory over the Grizzlies, he'll be on his way back.

"This is a special run for me," Duncan said. "I really want to get this one done. I really want to get back to the Finals. I want to win another championship."

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