“I’m really living my dream,” he said in a recent interview.

Any Spurs player could be forgiven for pinching himself. Halfway through an N.B.A. season dominated by the defending champion Golden State Warriors — who jumped to an unprecedented 24-0 start and are now 40-4 — the Spurs’ season has been every bit as golden as the bridge depicted on the Warriors’ uniforms.

The Spurs are 38-6, are unbeaten at home and have a better point differential than the Warriors. If not for Stephen Curry, who is becoming, 3 points at a time, the new face of the N.B.A., Spurs forward Kawhi Leonard would probably be the leading contender for the Most Valuable Player Award. The first of four regular-season matchups between Golden State and San Antonio, the league’s two best teams, is set for Monday night in Oakland, Calif.

Boban Mania, as the frenzied acclamation that seems to accompany Marjanovic’s every move has been labeled, has been one of the more attention-grabbing subplots of the Spurs’ season, and Marjanovic has become the N.B.A.’s biggest star — physically, anyway — along with the Knicks’ 7-3 Kristaps Porzingis.

Although Boban Mania is indigenous to the Spurs’ AT&T Center, where Marjanovic’s entries are greeted by thunderous cheers, it has also cropped up in Brooklyn and Philadelphia, where Marjanovic’s stellar play in the final minutes of routs has earned applause from enemy crowds. An unofficial Twitter account, @didbobanplay, answers the question posed by its name every time the Spurs play. This month, dozens of fans, including a man with a sketch of Marjanovic shaved into his head, showed up for Marjanovic’s autograph-signing at a San Antonio restaurant.

While some of Marjanovic’s statistics are fantastic — he had the N.B.A.’s third-highest player efficiency rating, just ahead of Russell Westbrook and behind Curry, entering Friday — they result from his playing sparingly, typically in blowouts against weaker opponents (he had played in just one of San Antonio’s six losses heading into the weekend). In the Spurs’ 117-89 victory at Phoenix on Thursday, he had his first N.B.A. double-double.