Apr 16, 2025; Sacramento, California, USA; Dallas Mavericks head coach Jason Kidd reacts to a call during the fourth quarter against the Sacramento Kings at Golden 1 Center. Mandatory Credit: Sergio Estrada-Imagn Images Sergio Estrada-Imagn Images

Dallas Mavericks lose coaching staff member to San Antonio Spurs

Originally posted on Dallas Mavericks on SI
By Keenan Womack | Last updated Jun 22, 2025 8:09 PM ET

Since the days of Dirk Nowitzki and Tim Duncan, the Mavericks and Spurs have always had a fierce rivalry, with San Antonio leading the all-time series 136-103. They have met in the playoffs and battled in the regular season for decades, amplifying tensions when the stakes were higher. Two franchises defined by different styles over the last 25+ years, San Antonio has won five championships to the Mavericks' one.

No matter what time of the season it is, this feud is one of the fiercest in Texas sports, despite its lopsided nature. Today, a new chapter of the I-35 Rivalry has been written – this time, off the court.

According to NBA Insider Shams Charania, Dallas Mavericks assistant Sean Sweeney has agreed on a deal to become the associate head coach of the Spurs under Mitch Johnson. An in-demand commodity in the basketball field, Sweeney had taken interviews for elevated positions elsewhere, but landed just down the road for the Mavericks' bitter rivals.

Dallas Mavericks assistant Sean Sweeney has agreed on a deal to become the associate head coach of the San Antonio Spurs under Mitch Johnson, Andy Miller of Klutch Sports tells ESPN. Sweeney has interviewed for coaching jobs in recent years and now departs Mavs for elevated role. pic.twitter.com/ohfgseOqCf
— Shams Charania (@ShamsCharania) June 22, 2025

Beyond the jump in position for Sweeney, who moves from assistant to associate HC, the move makes sense for on-court reasons. Each franchise is moving in drastically different directions; Dallas is backsliding after suffering a miserable 2024-25 campaign marred by self-inflicted wounds and devastating injuries, while the Spurs are beginning to find their footing behind the elite two-way capabilities of Victor Wembanyama.

Had there been stability within the Mavericks organization and front office, this may have been more avoidable, but with the level of ineptitude displayed by Nico Harrison and Patrick Dumont, it is not difficult to understand why Sweeney took the job beyond its title. Dealing away Luka Doncic and Quentin Grimes, on top of firing Casey Smith and installing an unqualified medical staff, the problems for the Mavericks continued to accumulate throughout the 2024-25 season.

Sweeney's departure marks a major change to the Mavericks organization, as he was a key piece of Kidd's staff on multiple fronts. The fact that he moved to a bitter foe only adds insult to injury, but also illustrates just how well-respected Sweeney is in coaching circles around the NBA. The Mavericks will have to find a replacement elsewhere or promote from within to fill the void left behind.

This article first appeared on Dallas Mavericks on SI and was syndicated with permission.

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