Kawhi Leonard’s health is the biggest variable for continuing the Spurs’ dynasty this year

On Sunday evening, Spurs coach Gregg Popovich announced that Kawhi Leonard will miss time with a partial tear in his left shoulder. The injury comes after a delayed start to Leonard’s season, as he missed over two months due to an ankle injury sustained in last year’s playoffs.

The Spurs have been good as ever without Leonard, rising to third in the West and a 27-13 record. But last year’s playoff loss against the Golden State Warriors served as evidence that the Spurs’ competitive hopes fall apart in the playoffs without Leonard.

San Antonio has always been most successful when their stars are rested and healthy for the playoffs. Every team benefits from health, and every team has to weather the storm of injuries each season, but it’s an ingredient in the Spurs’ dynasty that goes unnoticed too often.

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Duncan’s career low in games played (outside of two lockout-shortened seasons) was in 2004-05, when he appeared in only 66 games, in part due to an ankle sprain near the end of the regular season. But they won the championship that year — the more impactful injury situation occurred in 2000. San Antonio had just won a title the previous year, and appeared on the verge of an elite run behind players like Duncan, David Robinson and Avery Johnson. However, Duncan tore his meniscus at the tail end of the regular season that year, and Popovich was faced with the decision of whether or not to bring his star back for the playoffs to chase a repeat.

Popovich chose to give Duncan the time for recovery, deactivating him for the entire playoffs and forfeiting competitiveness (the Spurs still made it to the conference finals).

There are no second, third, fourth or fifth championships without Manu Ginobili and Tony Parker. Stars two and three have also stayed remarkably healthy, with no major injuries or entire seasons lost. They both played nearly every game through the fourth title, at which point they each began to miss more time. Ginobili posted seasons of 34 and 44 games played between 2008 and 2012, while Parker sunk to 56 in 2009-10. Both remained in the 60s or higher through this season, in which each has stayed healthy.

The whole San Antonio system flowed outward from Duncan, and from those two as extensions of him. Each Spur plays with unselfishness, defensive intensity and patience thanks to the lessons they learn from Duncan, Ginobili and Parker. Time on the court builds these habits, as do hours together working off the court. If guys aren’t at work every day, development is a stalemate.

In the past several seasons, more than a few championship contenders have detonated because they could never quite get healthy at the right time. Injuries have impacted several recent titles as well, drawing focus on how lucky and careful the Spurs have been. Oklahoma City’s stars seemed to alternate injured seasons at the end, while Golden State narrowly lost in 2016 after Steph Curry’s ankle tweak in the second round. Cleveland lost Kevin Love and Kyrie Irving in 2015, while Los Angeles could rarely count on Blake Griffin and Chris Paul to come out any series unscathed.

San Antonio has had playoff failures, including a Memphis sweep in 2012 and in 2009, when Ginobili missed the playoffs and Dallas beat them in five games. But rarely have their failures resulted from injuries or exhaustion.

This summer, the NBA voted at its annual Board of Governors meeting to adopt changes to its resting policy. Commissioner Adam Silver urged teams to, “find that right balance between resting on one hand and obligations to fans and partners on the other.”

We don’t yet know how this will impact championship contenders’ health heading into the 2018 playoffs, but MIA star players have not been a narrative of this season as in years past. Consistently finding opportunities to rest players has been a valuable strategy for Popovich throughout his career, and the team has accepted fines on his behalf for doing so.

By staying in tune with trends in sports science and generally shirking the brutality of the NBA schedule (even at the behest of the league), San Antonio has won with the same core for nearly two decades. They have ushered in a new group without missing a beat, constantly prioritizing depth and a flexible system over traditional star-level usage. It started with Duncan, but continues today.

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The Spurs have gotten lucky, but they also practice — better than anyone — habits which create a healthy, rested roster come playoff time.

Leonard currently faces the unknown, which could be something prolonged like his early season absence or end as early as Thursday, like some reports have already offered. LaMarcus Aldridge has had a fantastic season without Leonard, steadying the ship on offense. Yet even teams as dominant as the Spurs have no chance to compete at the highest level when their star is off the court.