Mavs' Cooper Flagg Rookie Trading Cards Surging in Value

If Cooper Flagg's potential to be a once-in-a-lifetime talent in the NBA wasn't justified by his recent Rookie of the Year win last month, it can also be determined by his influence across all sports in one of fans' fastest-re-emerging hobbies: trading cards.

Following what was reported as a "record-breaking" 2025 for grading athlete trading cards, the first quarter of 2026 has proven just as profitable.

Flagg is a big reason why.

According to GemRate's research of which companies are grading the most trading cards, PSA, who is known as the industry leader, has seen a strong surge in popularity in the rookie cards of the Dallas Mavericks star.

Of course, these are the last few times Flagg can still be considered a "rookie." So, as cards are being printed before he begins Year 2, people are getting desperate to get their hands on them. The rest of Flagg's career is sure to boost each rookie card's value more and more as it ages.

In April, Flagg cards were the most graded basketball cards, topping iconic names such as Michael Jordan, LeBron James and Kobe Bryant. San Antonio Spurs big man Victor Wembanyama was also near the top of the list as he emerges into a superstar, currently leading the Spurs into the second round of the playoffs.

Even more impressive, Flagg ranks second overall in graded cards for the month. He sits only behind baseball's Shohei Ohtani, the two-way specimen for the Los Angeles Dodgers that is already receiving G.O.A.T consideration.

Flagg saw a boom of +18 percent from March to April in his graded cards, which is a trend that coincides with his strong surge toward the ROTY title where he was the only player in the NBA to average at least 22.6 points, 6.9 rebounds, 5.4 assists, 1.2 steals and 1.2 blocks per game after the All-Star break.

Knueppel actually had the most drastic uptick in growth, with a 47 percent jump from month to month as he helped the Charlotte Hornets to the playoffs and showed legitimate odds of stealing the ROTY award from the No. 1 overall pick and his former college teammate.

Flagg's popularity over Knueppel, however, is overwhelming when you look at the number of graded cards. There have been over 30 thousand Flagg cards graded on PSA's metrics, compared to just below eight thousand featuring Knueppel.

Whether it's on the hardwood or in the hobby, Flagg is proving that his arrival in the NBA is anything but ordinary.

Flagg's stellar rookie season is officially transitioning into the offseason, but before he reaches sophomore status, collectors may continue to rush to lock in what may soon be considered vintage gold.

The trading card market is doing what it has always done best: betting on greatness before the rest of the world can catch up.

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