Cooper Flagg's potential fit with the Mavericks and his fantasy basketball potential as a rookie

Every so often, the unpredictable happens in sports, and that’s exactly what unfolded for the Mavericks during the 2025 NBA Draft Lottery. With a slim 1.8% chance to snag the top pick, Dallas came out of nowhere to pull off an unprecedented miracle. 

Some will say it’s rigged. Maybe the basketball gods are making the Lakers atone for their sins in fleecing Nico Harrison. Either way, that stroke of luck might have given a disgruntled Mavericks fan base hope in landing the top player in the 2025 NBA Draft, Duke’s Cooper Flagg. Flagg fits Harrison’s “defense wins championships” mantra. For fantasy basketball managers, Flagg could start right away for a contending team with ample talent and experience to expedite his development and impact as a rookie.

Year 1 expectations for Cooper Flagg

Flagg walks into the NBA with the spotlight firmly on him. It’s never easy having the pressure of being the consensus and projected No. 1 overall pick. Here’s how former first-round picks have performed in fantasy basketball over the past 10 years.

This is not a great representation of success, considering only three top picks from that 10-year period (Towns, Wembanyama and Ayton) finished in the top 100 in their rookie seasons. However, Flagg was in a tier of his own after just one season at Duke, capturing nearly every notable accolade in his conference and on a national level.

His first-year numbers at Duke were solid across the board, displaying plenty of cross-categorial appeal in fantasy.

19.2 points, 7.5 rebounds, 4.2 assists, 1.4 3s, 1.4 steals, 1.4 blocks, with 48/39/84 shooting splits

Flagg’s ability to wreak havoc defensively makes him a special prospect out of the gate. His instincts, length and timing are incredibly advanced for his age (18), making him a disruptive force in passing lanes or contesting shots. Whether switching on guards or battling in the paint against power forwards, Flagg’s versatility and motor set him apart.

His offensive game will take time to fully develop, but his efficiency shows that there is a strong baseline to evolve. The jump to NBA defenses will be an adjustment, so if his jumper isn’t falling immediately, it’s great that he has other ways of impacting the game. Flagg is also a willing and capable playmaker, averaging over four assists per game. 

I’m still reminded of his scrimmage with Team USA this past summer, where he turned heads and made a name for himself among the best in the game.

For now, Flagg’s defense will be his calling card, earning him immediate playing time as he adapts to the NBA. He has the prototypical size of a forward who can defend and play multiple positions. He may not light up the scoreboard immediately, but his high-impact, all-around contributions give the Mavericks a versatile two-way player to build around. 

Think of him as a modern-day young version of Andrei Kirilenko — a defensive menace with the athleticism and versatility to round out his game as his career progresses. I don’t typically draft rookies in fantasy, but Flagg is an exception. I would spend a mid-to-late round pick in any format for the defensive upside with some scoring and low-key assists. 

Given the underwhelming history around first overall picks in fantasy, he’s more likely to be a top-100 player than top 50. There will be a substantial hype train heading into next season, so don’t be surprised if someone in your fantasy league takes him ahead of his ADP. I’ll be targeting him by the eighth round in 9-cat leagues. 

The Mavericks lucked up

Trading Luka Dončić to the Lakers halfway through the season in a blockbuster deal that brought in Anthony Davis and Max Christie marked a dramatic shift for the franchise. After a play-in exit, the Mavericks face a summer packed with tough decisions.

Kyrie Irving, recovering from a torn ACL, has a player option and is likely looking for an extension. If Irving opts in, Dallas retains a key piece for its future. The Mavericks might be left scrambling to replace his production and leadership if he chooses free agency. Irving’s decision could steer the ship in either direction for a team trying to balance rebuilding and contention.

Then there’s Daniel Gafford, the team’s energetic big man who’s entering the final year of his contract. He wants to get paid, and his market value is rising after a solid season. He’s one of the best rim runners and rim protectors available, but the Mavs still have Dereck Lively II. Dallas could include Gafford in a potential sign-and-trade, which could work to fill out the team’s greater needs.

Drafting Flagg is a no-brainer, and the Mavs reportedly will not trade his rights. His arrival doesn’t solve everything, but it makes the Mavs more dynamic with another two-way player who can help generate offense for a team that failed to do so in the postseason.

With Flagg in tow, the fantasy values of P.J. Washington, Naji Marshall and Klay Thompson would decline with the rookie taking more usage and opportunity share. I imagine the 2025-26 Mavs projected starting lineup (when healthy) will be Irving-Thompson-Flagg-Davis-Lively. If that happens, this team is closer to a contender than a rebuild, which is great for Mavs fans and fantasy managers.