BREAKING NEWS: Message: Former Oklahoma City Thunder National Basketball head coach Billy Donovan now with Dallas Mavericks as a top assistant coach, sent a message to Oklahoma City Thunder National Basketball head coach Mark Daigneaul concerning his…see more

In a stunning turn of events that has rocked the NBA coaching landscape, former Oklahoma City Thunder head coach Billy Donovan has accepted a new role with the Dallas Mavericks as their top assistant coach. The announcement, confirmed by multiple sources close to the organization, comes just days before the Mavericks are scheduled to open their training camp for the 2025–26 NBA season.

Adding to the drama, Donovan sent a heartfelt message to current Thunder head coach Mark Daigneault, reflecting on their shared history, Daigneault’s accomplishments with the franchise, and the future of the league’s coaching brotherhood. The message, which was shared publicly in a joint press release by both organizations, immediately sparked discussions across the basketball world.

This article explores Donovan’s unexpected move, the content and implications of his message to Daigneault, the strategic outlook for both the Mavericks and Thunder, and what this means for the coaching legacy of both men.

Part I: Donovan’s Return — A Coaching Giant in a New Role

A Surprising Move from Chicago to Dallas

Until recently, Billy Donovan was the head coach of the Chicago Bulls, a role he had held since 2020. Despite moderate success in Chicago — including playoff appearances but no deep postseason runs — Donovan’s departure in August 2025 caught many off guard. He cited “a desire to take a step back from head coaching responsibilities and refocus on player development and strategic innovation.”

Just weeks later, news broke that Donovan had joined the Dallas Mavericks as the top assistant under new head coach J.J. Redick, who was appointed following Jason Kidd’s departure after the 2024–25 season. The pairing of Redick, a first-time head coach, with Donovan, a seasoned bench leader, is already being labeled by analysts as one of the most intriguing coaching duos in the league.

Why Dallas?

According to sources close to Donovan, the opportunity to work with Mavericks stars Luka Dončić, Dereck Lively II, and newly acquired guard Zach LaVine was too enticing to pass up. “He sees Dallas as a title contender that needs veteran guidance on the bench,” said one league executive. “He’s not just there to assist — he’s there to mentor, advise, and help win a championship.”

The Mavericks’ front office has been vocal about their desire to add basketball intellect and playoff experience to their coaching staff. Donovan brings both, with two NCAA titles at Florida, five NBA playoff runs with OKC, and deep ties to player development.

Part II: The Message — Donovan’s Letter to Daigneault

Shortly after the announcement, the Oklahoma City Thunder’s media relations team released a joint statement from Donovan and Daigneault. In it, Donovan addressed the coach who once worked under him at both Florida and Oklahoma City.

Here’s an excerpt from Donovan’s letter:

“Mark, watching what you’ve done in Oklahoma City has been nothing short of inspiring. You’ve taken a young core and turned them into champions — not just once, but with consistency and class. Our time together built a foundation, but you’ve constructed the house, the street, the whole neighborhood.”

“I’m proud to have played a small role in your journey, and I look forward to competing against you. Iron sharpens iron, and I believe our battles will bring out the best in both our teams. Keep pushing boundaries, because you are shaping the future of basketball.”

The letter ends with a personal note:

“From Gainesville to OKC, and now from Dallas — I’ll always be rooting for you, except when we face off. Respect always.”

Part III: A Tale of Two Coaches

The Mentor: Billy Donovan’s Legacy

Billy Donovan’s career has spanned three decades. After back-to-back NCAA championships at the University of Florida (2006, 2007), he transitioned to the NBA with the Oklahoma City Thunder in 2015. His tenure included coaching legends like Kevin Durant, Russell Westbrook, Paul George, and Chris Paul.

Though he never brought a title to OKC, Donovan maintained competitive rosters, emphasized player accountability, and helped usher in the development of modern “positionless” basketball. He left the team in 2020 with a reputation as a builder and stabilizer — and as a coach who left a lasting impact on his staff.

The Protégé: Mark Daigneault’s Rise

Mark Daigneault, just 40 years old, has taken the NBA by storm. After serving under Donovan in Florida and the OKC Blue (G League), Daigneault rose to become head coach of the Thunder in 2020. Initially viewed as a long-term development hire, Daigneault quickly proved he was more than a placeholder.

Under his leadership, the Thunder rebuilt through the draft and shrewd trades. With stars like Shai Gilgeous-Alexander, Chet Holmgren, Jalen Williams, and Josh Giddey, Daigneault constructed a dynamic, unselfish, defensively elite squad. In 2025, he led OKC to an NBA championship — their first in franchise history.

Part IV: The Strategic Shift in Dallas

Why Bring in Donovan?

J.J. Redick, the newly appointed Mavericks head coach, openly advocated for Donovan’s addition:

“I needed someone who’s been in the fire. Billy knows playoff basketball. He knows how to manage egos, timeouts, pressure. I’m honored to have him alongside me.”

Donovan’s role will include:

• Leading game-planning and film sessions

• Advising Redick on rotations and end-of-game decisions

• Working closely with guards and wings in skill development

• Acting as a “second head coach” when needed

This role mirrors the model used by teams like the Warriors (with Mike Brown under Steve Kerr) or the Celtics (with Frank Vogel recently hired as senior assistant).

Inside the Mavericks’ New Look

With Luka Dončić entering his prime and LaVine’s explosive scoring added to the backcourt, Dallas is aiming for a Finals run. Donovan’s reputation for balancing star talent and system play could be crucial.

He’ll also work with Redick to refine defensive schemes — a known Mavericks weakness — and help young players like Olivier-Maxence Prosper and Jaden Hardy grow into reliable rotational pieces.

Part V: The League Reacts

Coaches’ Brotherhood Responds

Coaches across the league have weighed in on Donovan’s return and message to Daigneault:

• Erik Spoelstra, Heat head coach:
  “Billy’s always been a coach’s coach. Seeing him empower Mark says everything about his character.”

• Monty Williams, Pistons head coach:
  “I’ve seen few assistant hires get this much attention. But that’s Billy — he makes you better just by being around.”

• Gregg Popovich, Spurs head coach:
  “Smart move by Dallas. And classy gesture to Mark.”

Thunder Fans Show Mixed Emotions

On social media, reactions from Thunder fans were divided. Some applauded Donovan’s message and admired his support of Daigneault:

“Much respect to Billy D. A real one.” — @ThunderForever

Others were more skeptical:

“Is he really rooting for us from Dallas? Come on now…” — @OKCBaskethead

However, most acknowledged the deep ties between the two coaches and the pivotal role Donovan played in laying the foundation of OKC’s current success.

Part VI: What This Means for the Western Conference

Thunder vs. Mavericks — A New Rivalry?

The Western Conference was already competitive, but this move adds an emotional and tactical layer to OKC-Dallas matchups.

• Daigneault vs. Donovan
  While they won’t be head-to-head in title, they’ll be across benches, likely trading strategic counters.

• Player Connections
  Both teams are filled with rising stars. Every matchup now carries the subtext of mentor vs. protégé, old vs. new.

• Playoff Collision Course?
  If seeding aligns, a Thunder-Mavericks series could be one of the most anticipated matchups in years.

Coaching Legacy & Future Head Coaching Opportunities

Some insiders believe Donovan is positioning himself for another head coaching job in 2026 — or even a front-office role. With teams like the Kings and Nets reportedly monitoring his situation, this role in Dallas may be a one-year stepping stone.

Part VII: Final Reflections — Brotherhood Beyond the Bench

Billy Donovan’s message to Mark Daigneault transcends basketball. It’s a reminder of the lineage of coaching, of how lessons passed down can evolve and blossom into greatness in someone else’s hands.

Daigneault, gracious as ever, responded during a press conference:

“Billy taught me how to see the game as a whole, not just through the lens of wins and losses. His mentorship helped shape who I am today. I’m thrilled to see him back on a contender’s bench.”

Their story is not just about X’s and O’s — it’s about trust, mentorship, and the continuity of leadership in the NBA. In a league dominated by drama and short-term headlines, the Donovan-Daigneault connection offers something deeper: legacy.