Two weeks ago, the San Antonio Spurs were chugging along in typical Spursian fashion, winners of their first four games despite the absence of Kawhi Leonard. The collective basketball world gushed about their ability to grind out victories. They looked destined for a sixth consecutive 55-win season.

Fast forward, to now, and the Spurs may still reach that total. But without Leonard, cracks are beginning to show.

Over the last seven games, they are 3-4, with their victories coming against a middling Charlotte Hornets squad, the overmatched Phoenix Suns and the reeling Los Angeles Clippers. Even if they win a couple more on the trot, this recent stretch has revealed two main issues. First, their roster has serious offensive flaws. And second, although head coach Gregg Popovich is a sorcerer, he needs Leonard to cover up those flaws.

The Spurs’ defense has been stingy. It’s allowing just 102.6 points per 100 possessions—a mark which would’ve ranked third in the league last season. And while other teams will regress over a greater sample size, their defense has shown it can hold up without Leonard. Last year, they surrendered just 96.0 points per 100 possessions when he sat. Some of that success was anomalous, but it shows how solid San Antonio’s other defenders continue to be.

Popovich still plays two traditional bigs, a proven recipe for regular-season success on defense. In the backcourt, Dejounte Murray and Danny Green are quick, rangy and smart. Patty Mills is a pest. Even Rudy Gay and Brandon Paul have proven to be switchy defenders who can strap up opposing bench units. Would Leonard improve the Spurs’ defense? Of course. He’s a two-time Defensive Player of the Year. He takes opposing stars out of the game and comes up with timely blocks and steals. But Popovich has found ways to cover for his absence.

Offense is a different story. The Spurs rank 19th in points scored per 100 possessions with 102.9, down from 108.8 last season. Sure, Tony Parker’s absence hasn’t helped. But he’s 35 and, at this point in his career, nothing more than a fringe starter. Leonard is the true loss.

LaMarcus Aldridge has taken over as San Antonio’s first option in his stead, and to be fair, he’s performed admirably. Everything—every post-up, every dribble handoff, every pick-and-roll—runs through the 32-year-old. His usage rate of 28.1 percent is the highest of any San Antonio big man since 2008-09, and he currently paces the league in post-up possessions. The Spurs have a 105.0 offensive rating when he’s in the game. That number plummets to 98.2 when he’s on the bench.

But even if Aldridge continues in this form, it won’t  keep the Spurs afloat. Regardless of the results, plays like these are bad offense, and they’re all too common in an Aldridge-centric attack:

Look up and down San Antonio’s roster, and you can see why Popovich is so reliant on his star big man: No one else can get to the rim and create offense. Murray is raw and still learning the nuances of the game. Green is a pure spot-up shooter, though he’s shown he can do more when called upon this season. He’s shooting 45.8 percent on five drives per game, up from 37.5 on 1.6, respectively, last year.  Mills is a roadrunner, but he’s at his best zooming off screens for open threes. And without the threat of penetration, opposing teams don’t need to cheat off shooters like him to help elsewhere.

Enter Leonard.

Last season, he ranked in the 94^th percentile in scoring efficiency out of the pick-and-roll and the 73^rd percentile in isolation. He can dominate a game from every part of the court—beyond the arc, the elbow, the low-post. But, most importantly, he has become lethal off the bounce. He scored on 63.7 percent of his drives and shot a solid 42.5 percent on pull-up jumpers last year.

Leonard attracts a ton of attention from help defenders as a result. His ability to collapse the defense allows San Antonio to ping the ball around and find open shots. That the Spurs scored 30 points per game on catch-and-shoot jumpers last season but have managed just 24.6 this time around is telling. And although they’ve had more wide-open shot attempts, they’ve plummeted down the league rankings in that category, from eighth to 23rd.

These looks just don’t materialize without Leonard:

If Aldridge is San Antonio’s key avenue for shot creation this season, Leonard was even more integral to the offense last year. His 31.1 percent usage rate was the second-highest of the Popovich era, and over half his made field goals were unassisted. At times, Popovich basically handed him the ball and told everyone else to get out of the way. Leonard could usually create something for himself in those situations. If not, he could at least force the defense to panic and leave passing lanes open.

That style is not San Antonio’s typical bag, but it worked anyway. The Spurs managed 112.6 points per 100 possessions with Leonard on the court, compared to 102.6 when he rested. That disparity grew even further in the playoffs—plunging from 117.6 to 101.9 when he rested.

As Matt Moore of CBS Sports wrote back in April: “Leonard is used as the tip of the spear in the Spurs’ offense. The whole team’s construct is built to get him quality looks.”

That tidbit is only partially true. Leonard isn’t merely the beneficiary of Popovich’s system; he makes the system work. Unless Leonard is involved in the final action as a do-everything scoring threat, the whole play profiles as meaningless.

Just compare this Mills pick-and-roll:

To a nearly identical Leonard pick-and-roll:

Popovich, who once helped spark the corner-three revolution, isn’t a basketball purist. He wants to win. And he knows playing a pretty style is pointless if you can’t put the ball in the hoop.

Dumping the rock to Aldridge may work every so often as an alternative. Absent Leonard, though, the Spurs won’t create enough quality looks and don’t have anyone to sink the more difficult ones.

Take away the tip of the spear, and you have no spear at all.

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Unless otherwise indicated, all stats are from NBA Math, Basketball Reference or NBA.com and are accurate heading into games on Nov. 1.

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