The San Antonio Spurs soon have to face the harsh reality that longtime head coach Gregg Popovich is set to retire. When a legendary coach of his stature hangs it up, the first question is always who's in line to replace him.

According to Bleacher Report's Jake Fischer, two of the Spurs' most iconic figures in Tim Duncan and Manu Ginobili have often been mentioned as candidates for the job.

However, the prospect of Duncan taking on coach Pop's mantle may be more fantasy than reality for Spurs fans. He did serve as an assistant coach for a spell, but stepped down shortly after.

Manu Ginobili taking on the role makes a bit more sense. The Argentinian has recently joined the Spurs staff and reportedly has the chops to do it. But given he hasn't even had a true taste of coaching on the sidelines, it may take a season or two for him to get fully acclimated enough to take on the role.

Via Bleacher Report:

Recently, Manu Ginobili's name has surfaced after the champion guard rejoined the Spurs in a nebulous basketball operations role. “If there's a former player who has the basketball IQ and the EQ to do it, it's Manu,” another veteran executive with knowledge of San Antonio said.

Yet it would seem there are no direct plans for Ginobili to join the Spurs' coaching staff full time, and few, at this juncture, expect San Antonio to choose a Popovich replacement with zero experience on an NBA bench.

Former Spurs assistant Will Hardy is reportedly a strong candidate for the job. The Popovich coaching tree product is currently working for the Boston Celtics under Ime Udoka. His coaching resume makes his hiring a bit more feasible than the aforementioned Hall of Famers.

While the favorite for the spot is unclear, one thing's for sure. Whoever takes over the Spurs coaching duties once Gregg Popovich retires will have some massive shoes to fill.