Where do the San Antonio Spurs go from here?

We might have witnessed the end of an era Thursday night when the Oklahoma City Thunder bounced the San Antonio Spurs from the playoffs with a lopsided 113-99 win. Immediately after the buzzer sounded in Chesapeake Energy Arena, even in the middle of the celebration the home crowd had to wonder if it was the last time they’d see Tim Duncan and the rest of San Antonio’s aging stars grace the hardwood.

Duncan is 40 years old and in his 19th season in the NBA. Along with Tony Parker and Manu Ginobli, he was part of a “Big 3” long before players jumping ship to form “super teams” was cool. Ginobli is 38 and Parker is 33, but don’t let their age fool you–both have played extensively on the international circuit and have a lot more wear-and-tear on their bodies than most players. Duncan and Ginobli both have player options for next season, and both will take the offseason to evaluate whether or not they will return.

Arguably the best power forward of all-time, Duncan averaged just 5.9 points and 4.8 rebounds over 21.8 minutes in the postseason. Parker and Ginobli didn’t fare much better, with Parker averaging 10.4 points and Ginobli adding 6.7. Kawhi Leonard, the team’s cornerstone of the future, led with 22.5 points while LaMarcus Aldridge added 21.9. Other than Parker, no other Spurs player averaged double-figures. This doesn’t bode well for San Antonio going forward.

The Spurs looked a couple steps slower than the Thunder all series long. Even though they managed to get two wins and push the series to six games, those victories came after extended rest. Leonard (24) is a two-time Defensive Player of the Year and a former NBA Finals MVP, so he’s a great foundation piece. But nine out of the 15 players on San Antonio’s roster are on the wrong side of 30, including Aldridge, Leonard’s presumed running-mate for the future.

The thing about San Antonio is that any player, young or old, superstar or average, can flourish in Gregg Popovich’s motion-offense system. So is age really the problem? Yes, it is. The Spurs won 67 games this year, but they unexpectedly slowed down in the second round of the playoffs when pundits were predicting they’d reach the NBA Finals. San Antonio must address this issue in order to really contend with teams like Oklahoma City and the Golden State Warriors.

Some younger, more athletic forwards would work wonders in the long run. The Spurs like to play a traditional lineup, but with more and more teams imploring small-ball strategy, it’s important that they make adjustments as well. Aldridge also isn’t the defensive force down low the way Duncan, an eight-time all-defensive first team selection, once was. Putting some players next to Aldridge who can alleviate the defensive burden will also be important to San Antonio’s success. An unrestricted free agent like Hassan Whiteside would work very well next to Aldridge. DeMar DeRozan, a rangy wing and Mike Conley, the consistent and continually underrated engine that drives Memphis, will have to be on the table for the Spurs brain trust to consider as well. Conley in particular could fit in seamlessly with the Spurs. Picture it: a humming offensive orchestration run by Conley with Aldridge and Leonard creating spacing and mismatches, while defensively Conley has the grit and quickness to slow down most of the West’s elite point guards.

San Antonio cannot wait around for Duncan and Ginobli’s decisions whether or not to retire. If the Spurs don’t get younger, they would be relegated to a dominant regular-season team that falters in the playoffs. And let’s face it, this is the Spurs. An organization that has advanced to six NBA Finals in the past 17 seasons, claiming five of those titles. They make the right calculations, they have an unwavering conviction in their system and with or without Duncan and Ginobili, they still have the system and process in place.