Imagine an NBA general manager who, mid-season, fires the coach with the best winning percentage in franchise history.

Then, despite having no head-coaching experience outside something called Pomona-Pitzer, the general manager names himself head coach.

He goes 17-47 the rest of that season. Yet, he lucks into the No. 1 pick in the draft and selects the arguably the most NBA-ready rookie of all-time, a future Hall of Famer to pair with the one his team already has. Then, with two future Hall of Famers, he wins just one playoff series. In year three, he starts 6-8.

Think that coach belongs on the hot seat?

Well, Gregg Popovich was in 1999.

By March 2 of the lockout-shortened 1999 season, the Spurs coach faced intense scrutiny from within and outside the organization.

Marc Stein of ESPN:

A popular former Spur named Doc Rivers also happened to be a member of San Antonio’s broadcast team in those days. The fans’ clamor for Rivers, who was already being billed as a coaching natural, to replace the what-has-he-ever-done Popovich got louder with every loss suffered during that slow start. But by the time the Spurs were headed to Houston for the 15th game of a truncated schedule that left no time for early slumps, pressure on Pop wasn’t coming solely from the public or the media. The belief among many of Pop’s players was that the coach was on the brink of being fired. Or being forced, at the very least, to return to a GM-only role. “It was different from the regular pregame,” former Spurs forward Malik Rose said, rewinding back to the game in question against a Rockets team headlined by Hakeem Olajuwon, Charles Barkley and Scottie Pippen. “David [Robinson] usually didn’t say much beyond a prayer in the huddle when we brought it all in, but [before this game] David was saying, ‘We’ve got to get it together, we’ve got to do this, this is a big game.’ “If we lost that game, they were going to fire Pop and bring in Doc … that was the rumor. I would have to say it was real because of the gravity in the locker room. I’ll never forget it.” Said then-Spurs guard Steve Kerr: “I can’t say I felt like he was close to getting fired, but there was a lot of discomfort with the way things had started [that season]. Pop wasn’t Pop yet. He didn’t have a name. The fans still didn’t really know who he was.”

[Avery] Johnson, Pop’s point guard and the most vocal of leaders on that Spurs team, says today that he has no doubt that Houston game was the ultimate must-win for the third-year head coach. “Absolutely,” Johnson says. “Things had been communicated to us. It was really real. “There was a lot of noise about Pop being potentially replaced by Doc, so David [Robinson] and I went to Pop’s house before we got on the flight to go to Houston. Pop talked to us and … what I will say is we came out of there feeling so strongly about Pop that we knew we had to go win that game.”

“I don’t know that I’d say the end was near,” said longtime Spurs assistant coach Mike Budenholzer, now coach of the Atlanta Hawks. “But there was a real concern that we weren’t meeting expectations. It was real. It was genuine. We knew we needed to start playing better and start playing better soon. So I would say it was real.” Said Johnson: “At the end of the day my allegiances were to Pop because he had put such great faith in me. I felt if he would have gotten fired [after replacing Hill], I’d have been one of the reasons he got fired, because I wasn’t viewed as a starting point guard that could lead a team to the championship. So I really took that personal. [And] it was the most passionate pregame speech David ever gave. He was foaming at the mouth.”

The Spurs beat the Rockets by 17, sparking a 31-5 finish to the regular season and a run through the playoffs that ended with a championship. Popovich obviously stuck around, and Rivers eventually broke into coaching with the Magic.

Yet, this story – one of many told by Stein in an excellent feature on Popovich and Duncan – leaves so many fun and unknowable questions unanswered. The two that stand out to me:

How would Rivers had done with the Spurs?

Was Popovich already a great coach in March 1999, or did this one win give him time to grow into the job?

This – what if the Spurs had lost to Houston that Tuesday night? – is definitely one of the great what-ifs in NBA history.