Why did Klay Thompson leave Warriors for Mavericks? How free agent decision impacts Luka Doncic, title race & more

The Splash Brothers are breaking up.

Monday marks the end of an era, as star wing Klay Thompson is headed to the Mavericks in a multi-team sign-and-trade involving the Warriors and Hornets, per ESPN's Adrian Wojnarowski.

The writing was on the wall for Thompson's time in Golden State. Now, it has become a reality after he agreed to a three-year, $50 million contract with Dallas. The deal is "not close" to being completed, per Bleacher Report's Chris Haynes, as the Warriors still need to negotiate their return for Thompson.

Regardless, the result will spell the four-time NBA champion's departure from the franchise that selected him 11th overall in the 2011 NBA Draft.

Why did Thompson leave the Warriors and what does it mean for the Mavericks? The Sporting News breaks it down below.

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Why did Klay Thompson leave Warriors for Mavericks?

Thompson's exit from Golden State became the worst-kept secret in free agency.

There were several reports throughout the 2023-24 season that Thompson's time with the Warriors could be coming to a close. Those rumblings grew even louder when The Athletic's Anthony Slater reported that "there's been no productive discussion between the Warriors and Thompson or his representatives" just days before free agency began.

"It has become increasingly conceivable that Thompson will decide to leave regardless, searching for a fresh start in a different environment, detached from some of the built-up friction of the previous couple seasons," Slater added.

Thompson built a future Hall of Famer career over 13 seasons with the Warriors. He and Stephen Curry changed the trajectory of the sport with their 3-point shooting flurries, collecting four NBA titles in the process.

Thompson's relationship with Golden State wavered over the last few seasons, though. It was clear he was not the same player after recovering from ACL and Achilles injuries, and his role was reduced because of it. The five-time All-Star was relegated to a role off the bench in the second half of this past season — a decision he didn't take fondly.

When the Warriors failed to qualify for the 2024 NBA Playoffs, reality set in that it could be the end of the dynasty core. By the time Thompson's unrestricted free agency hit, it became a foregone conclusion.

Thompson reportedly met with the Mavericks and Lakers but chose Dallas in pursuit of a possible fifth championship ring. Both teams could have offered him similar money, but the Mavericks were only three wins shy of an NBA title this past season.

Thompson felt Dallas was his best chance to prove he can still be a key piece to an NBA Finals run.

MORE: Who should Lakers target after missing out on Klay Thompson?

Klay Thompson

(Getty Images)

How Klay Thompson fits with Luka Doncic, Kyrie Irving and Mavericks

It's pretty easy to see how Thompson could thrive next to Doncic and Irving.

Even with his post-injury limitations, Thompson is still one of the greatest marksmen in NBA history. He is a career 41.3 percent 3-point shooter with the sixth-most triples of all time.

In a "down year" last season, he still shot 38.7 percent from beyond the arc and 38.1 percent on catch-and-shoot 3s.

With Derrick Jones Jr. and Tim Hardaway Jr. leaving, Dallas needed to add more perimeter shooting. Thompson is a clear upgrade over both of those options who struggled at various points of its 2024 NBA Finals run.

Josh Green is reportedly heading to Charlotte in the deal, but the Mavericks have added other wings in Naji Marshall and Quentin Grimes this offseason. Those two will be asked to fill the defensive void left behind by Jones and Green because Thompson is nowhere near the player who was once voted to an All-Defensive Team.

Thompson's offensive contributions will be a relief for Dallas' two stars, but his lack of mobility on defense could be a cause for concern come playoff time.

MORE: Did Mavericks or Pistons win Quentin Grimes trade?

What Klay Thompson's decision means for Warriors

The Warriors have already begun to pivot from Thompson's exit.

While it waits for its return in the Thompson sign-and-trade, Golden State signed two-way guard De'Anthony Melton to a one-year, $12.8 million contract. Melton won't slot into the starting lineup, but he'll provide depth off the bench.

The Warriors are expected to be active in the trade market, with players like Andrew Wiggins reportedly available. Golden State has also popped up in trade rumors around All-Star forward Lauri Markkanen if Utah looks to deal its biggest trade piece.

On the immediate roster, look for second-year wing Brandin Podziemski and 22-year-old wing Moses Moody to step into a larger role, pending other transactions this offseason.