The two coaching lions have battled each other for decades, winning some battles, losing others, trading barbs along the way that only men of their stature could dare say.
So when Popovich heard, like the rest of us, that Jackson might be on his way back to the Lakers sideline he had to smile.
"I did have kind of a strange thought," Popovich said. "I just had this thought that it was like putting the Soviet Union back together again. Let's go get Putin and put it all back together. Because I'm a strange person, that all went through my head."
So if the Lakers are the Soviet Union and Jackson is Putin, what does that make the Spurs?
"We're Ammerrrica," Popovich joked with a funny accent.
Jackson, of course, was passed over by the Lakers for Mike D'Antoni in a stunning move late Sunday night and not in position to fire a barb back across the aisle.
But knowing him, he would've enjoyed the opportunity to do so. Whenever he and Popovich get into it -- whether it be on if the Spurs' title in the lockout-shortened season deserved an asterisk or something lighter, like Jackson's feelings on the charm of San Antonio's River Walk -- it's always entertaining.
Whether there's actual ill-will behind the verbal sparring, one can only guess, but there is definitely a mutual respect.
"We never really knew each other that well at all. We waved to each other before the game, that's all," Popovich said, when asked if his relationship with Jackson extended off the court. "But Phil's Phil. He's the all-time best. What else can you say? He's somebody that commanded a lot of attention and deservedly so."