Another NBA Finals opens in San Antonio.

Mike Brown was on the bench — in what is now known as the Frost Bank Center — with Gregg Popovich during the 2003 NBA Finals, serving as a young assistant in the title series against the Nets, which ended with a parade along the San Antonio River.

Four years later, Brown was a second-year head coach with a 22-year-old superstar (LeBron James), attempting to lead the Cavaliers to an upset of Tim Duncan’s Spurs.

Now, Brown, 56, is heading back to a city where his family still resides, needing to defeat the friends and the franchise that helped catapult his career to claim his first championship as a head coach.

“They definitely want to beat me and I want to kick their ass,” Brown said following Sunday’s practice. “You love ’em and you can always love ’em before and after … I got ties to San Antonio and you appreciate the people, you appreciate the journey and all that other stuff. But at the end of the day, just like they want to beat you, you definitely want to beat them.”

Brown was a hard-working but relatively inexperienced 30-year-old when he arrived in San Antonio, where he’d spend three years (2000-03) as an assistant who designed thorough scouting reports and color-coded practice itineraries.

Popovich (the five-time title-winning head coach who serves as the Spurs’ president of basketball operations) became a trusted mentor and close friend.

After Brown was fired as a head coach for the third time in 2014, Popovich helped convince him to unofficially end his coaching sabbatical by offering him a role as a volunteer consultant for the Spurs, giving Brown an open invitation to attend every game, practice and meeting he desired.

Brown, who had recently gone through a divorce, took up part-time residence in San Antonio — sleeping in a double bed, beneath a Spiderman poster, in the former bedroom of Danny Ferry’s son — and spent more than half a season with the Spurs, helping the coach he could never properly repay.

“The job that he’s done, not only on the court with that team and the organization, but off the court too, is gonna be imprinted as long as the game of basketball exists,” Brown said. “He still has a huge presence. He’ll always have a presence. His presence is very much felt all the time.”I’ve got a lot of respect for the organization for a lot of different reasons. I worked there, having an opportunity to work there and being part of a championship there and my family being down there too reminds me of good times.”