The Boston Celtics don’t own a lottery pick. They don’t have cap space. And yet, they’re at the center of one of the most intriguing draft rumors of the year: a potential trade-up for No. 1 overall prospect Cooper Flagg.
This hypothetical—first floated by The Ringer’s Kevin O’Connor—gained traction during the NBA Draft Combine in Chicago. Flagg remains the consensus top pick, and the Dallas Mavericks hold firm atop the board. While there are no confirmed discussions between the Celtics and Mavericks, Boston’s decision to use one of its 13 allotted combine interviews on Flagg drew attention and reignited speculation.
“At the draft combine this week, Tre Johnson openly said the Celtics interviewed him,” O’Connor said. “I have multiple sources telling me the Celtics also interviewed Cooper Flagg. Now, this does not mean they’re going to trade up into the top 10, but I do think it’s interesting.”
O’Connor laid out the framework: With Jayson Tatum expected to miss most of the 2025–26 season due to a torn Achilles and Boston lacking young, cost-controlled stars with franchise-altering upside, this offseason could be an inflection point. A trade package built around Jaylen Brown and multiple future first-round picks was the idea to theoretically get the Mavericks’ attention, if Dallas were even willing to listen.
“Boston calls [Dallas GM] Nico [Harrison] and they offer Jaylen Brown. And how many first-round picks is it gonna take? … I just wonder if Dallas and their entire decision-making unit would listen,” O’Connor said.
Flagg, 18, is widely regarded as a generational talent after a dominant season at Duke. He averaged 19.2 points, 7.5 rebounds, 4.2 assists, 1.4 blocks, and 1.4 steals on 38.5% shooting from deep. He also starred for the USA Basketball Select Team last summer and was named National Player of the Year a freshman.
He grew up in Newport, Maine—a die-hard Celtics fan in a region that has long embraced him as one of its own. That backstory and Boston’s surprise interview were enough to light up social media and fan speculation. But to this point, it’s still just that: speculation.
Dallas made the leap of a lifetime in this year’s lottery, jumping from No. 11 to No. 1 despite a 1.8% chance. The win gave the franchise a clean path to a post-Luka Dončić future, just months after sending their longtime star to the Los Angeles Lakers. The Mavericks do not have an interest in trading the pick.
Speaking on The Dan Patrick Show, head coach Jason Kidd made the team’s stance clear.
“We are playing for a championship,” Kidd said. “This isn’t about just rebuilding. He’s going to have help.”
Kidd emphasized Flagg’s youth—he doesn’t turn 19 until December—but believes the team’s veteran core, including Anthony Davis, Kyrie Irving, Klay Thompson, and Dereck Lively II, can support his growth without placing undue pressure on him from day one.
“This is a great situation for him,” Kidd added. “The pressure of living up to number one will be a lot easier with the talent around him.”
While speculation continues around potential trade scenarios, Flagg has kept his comments focused on the overall process, not any specific team. When asked about the experience at the combine, he reflected on the opportunity without referencing any particular destination.
“I’m grateful to get this opportunity, or any opportunity to hear my name called on draft night,” Flagg said. “I’m just really excited for this whole experience. Not everybody gets to go through this, so I just feel really blessed.”
He continued: “I think just trying to be present, trying to take it all in. You only get to do it one time. I’m trying to enjoy every second.”
Asked about playing with NBA veterans and adapting to the league, Flagg spoke about his offseason with the USA Select Team and how that helped prepare him physically and mentally.
“The biggest thing I took from it was the preparation—mental and physical,” he said. “I picked some of those guys’ brains… I just learned how important recovery is and how much attention you have to pay to it.”
Even if Boston wants to make a serious run at Flagg, it must overcome multiple hurdles. Jaylen Brown, who will be 29 before next season begins, is owed over $50 million annually through 2029. A trade would require parting with many rotation players since Flagg will be on a rookie-scale contract. With Anthony Davis starting a three-year deal worth $175.4 million and Kyrie Irving in line for a new contract, balancing the salary cap would be very challenging.
And while the comparison to Eli Manning’s 2004 NFL Draft standoff has surfaced in media conversations, there’s no indication Flagg or his camp are pursuing a move or targeting a specific team. He’s repeatedly emphasized his openness to wherever the process leads.
“Wherever it is, I’m just gonna try and be me to the best of my ability,” Flagg said. “Try to do whatever the team needs—play both sides of the ball and just play really hard in every single possession.”
The most likely outcome remains unchanged for now: Cooper Flagg hears his name called by the Dallas Mavericks on June 25 at Barclays Center in Brooklyn.
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