The Spurs haven’t had an NBA lottery pick since Tim Duncan went No. 1 in 1997, yet this year’s NBA championship roster was primarily built through the draft.

The Spurs’ ability to find talent outside of the top 14 picks is unparalleled in the NBA, and it’s the main reason they’ve been able to sustain a championship-caliber level for more than 15 years.

In 1999, San Antonio selected Argentinian guard Manu Ginobili with the second-to-last pick in the draft. Ginobili didn’t join the Spurs until after the 2002 FIBA world championship, but he was worth the wait.

Ginobili has scored 11,657 career points. The other 28 second-round picks in the 1999 draft have scored a combined 15,103 points — with Gordon Giricek leading the way at 3,670 points. Ginobili has also amassed 93.8 win shares over that span – fifth most of any player drafted in either round.

The Spurs’ next key addition came in 2001, when they selected Tony Parker with the 28th pick. Parker’s a six-time all-star, four-time NBA champion and 2006-07 NBA Finals MVP.

Out of the entire 2001 draft class, only Joe Johnson (who was picked 18 spots in front of Parker) has made more all-star appearances than the Spurs’ French floor general.

Then there’s the 2013-14 NBA Finals MVP Kawhi Leonard, whom San Antonio traded Indiana for on draft day in 2011. The Spurs gave up George Hill to acquire the small forward out of San Diego State. Leonard, 22, on Sunday became the youngest NBA Finals MVP since Magic Johnson in 1980. He went nine picks after the Wizards selected Jan Vesely.

Tiago Splitter and Cory Joseph, both drafted by the Spurs, were also key contributors on the Spurs this year.

Duncan, Ginobili, Parker, Leonard, Splitter and Joseph accounted for 68 percent of the points scored by the Spurs this postseason.

Spurs key draft picks

Here are the Spurs’ six players they drafted who had a big impact on this year’s title-winning team, and the draft picks taken one spot before and after them:

1997, Tim Duncan, No. 1 pick

Pick after: Keith Van Horn, 76ers

1999, Manu Ginobili, No. 57 pick

Pick before: Tim Young, Warriors

Pick after: Eddie Lucas, Jazz

2001, Tony Parker, No. 28 pick

Pick before: Jamaal Tinsley, Grizzlies

Pick after: Trenton Hassell, Bulls

2007, Tiago Splitter, No. 28 pick

Pick before: Arron Afflalo, Pistons

Pick after: Alando Tucker, Suns

2011, Kawhi Leonard, No. 15 pick (in trade with Indiana)

Pick before: Marcus Morris

Pick after: Nikola Vucevic

2011, Cory Joseph, No. 29 pick

Pick before: Norris Cole, Bulls

Pick after: Jimmy Butler, Bulls

But the Spurs’ roster will drastically change over the next few years.

The only player on San Antonio’s payroll for the 2015-16 season is Splitter. Duncan, Ginobili and Parker’s contracts all expire after the 2014-15 season, and each of them — as well as Coach Gregg Popovich — could decide to retire. Duncan is 38, Ginobili’s 36 and Parker’s 32.

With the 30th and 60th picks in this year’s draft, the Spurs will once again be challenged to find quality players outside the lottery.

The key to the Spurs’ future will be to re-sign Leonard, whose contract is also up after the 2014-15 season, and build around their young star. If San Antonio is unable to replicate its draft magic of the past two decades, it will be forced to rely on free agency.

This year’s squad has free-agent contributors Marco Belinelli, Boris Diaw, Patty Mills and Danny Green, but they were each low-budget flyers who ended up working perfectly in their system.

What will happen when the Spurs need to fill the shoes of their three biggest contributors of their past four NBA championships?

The Spurs have had the luxury of having modest stars who have been willing to take a pay cut to play for San Antonio. Parker, Duncan and Ginobili made just less than $30 million this year. In comparison, the Heat’s Big Three of LeBron James, Dwyane Wade and Chris Bosh made just less than $40 million.

It won’t be easy to find a free agent star on the open market willing to take a discount to play for San Antonio, especially if the Big Three are retired.

Jeffrey Tomik is the sports editor at Washington Post Express. Follow him on Twitter: @Tomiksports.