Spurs Assistant Coach in 40-40 club?

Although Gregg Popovich is as tough as coaches get, the NBA legend is 75. And yet the San Antonio Spurs head coach isn't too aged to have recently led the United States of America in the Olympics.

However, by most standards, he's getting rather long in the tooth for coaching. Obviously, the five-time NBA champion will likely retire in the next few seasons.

Perhaps the Spurs should prep for a replacement?

In a recent project curated by The Athletic, the publication concocted a 40 under 40 list. Spurs assistant coach Mitch Johnson earned a mention among the 40 professionals under 40.

Accroding to The Athletic's reporting, Johnson interviewed for the Toronto Raptors head coach vacancy last season. Johnson, as it happens, graduated from Stanford, showcasing an intellectual mind and basketball prowess.

During his eight years with the Spurs, Johnson spent four on Popovich's coaching staff.

The Spurs assistant coach cut his teeth interning at Seattle University before assisting on the Austin Spurs coaching staff. At a relatively young age, Johnson wouldn't be the youngest head coach in the league. Joe Mazzulla won an NBA championship at 35, the youngest head coach to do so since 1970.

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At 37, Johnson could take over once Popovich retires if the Spurs look to hire from within. While such a scenario is seemingly years away, it's worth a thought - and maybe worth trying to find a way to keep him around.