The early-season concerns over Cooper Flagg's play appear to be ancient history.
While it hasn't been a pretty season for the 10-16 Dallas Mavericks, their star rookie has turned a corner to his expected stardom in recent weeks, and that led to a new career-best performance on Monday night.
Taking on the Utah Jazz, Flagg topped 40 points for the Mavericks, although Dallas fell 140-133. Still, Flagg's outing was historic; he set a new NBA record for points by an 18-year-old.
Here's a look at Flagg's breakout night against the Jazz.
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Cooper Flagg stats vs. Jazz
Points: 42
Rebounds: 7
Assists: 6
Steals: 1
Blocks: 2
FG: 13-27
3P: 1-4
FT: 15-20
Coming into Monday, Flagg's season-high in scoring was a 35-point effort against the Los Angeles Clippers on Nov. 29. He topped that mark with ease against Utah.
The Mavericks fell to the Jazz, but Flagg was scoring from all around the floor, displaying the all-around talents that made him the No. 1 overall pick last summer. Particularly, he got to the free-throw line with ease, making 15 of his 20 attempts.
Flagg had 24 points at halftime against the Jazz, with his top highlight being a left-handed scoop that softly fell into the basket as he was fouled.
Cooper Flagg in just one half vs. Utah 😮
🔹 24 PTS
🔹 4 REB
🔹 4 AST pic.twitter.com/hZAZCfym6Y
— NBA on ESPN (@ESPNNBA) December 16, 2025
Later on, Flagg helped the Mavericks force overtime, floating one high off the glass with some light touch while trailing by three -- and he got the foul this time as well.
COOPER FLAGG IS HIM!!!! AND1 and he Has 39pts!! pic.twitter.com/lTrl6usJy0
— MavsHighlights (@MavsHighlights) December 16, 2025
Flagg added two points in overtime on top of his seven rebounds and six assists, but Dallas fell as Keyonte George dropped 37 points for Utah.
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Highest-scoring games by 18 years old in NBA history
Flagg had already been threatening to break the NBA record for most points in a game by an 18 year old, as his 35 points earlier this season were the third-most ever. On Monday, he officially took claim of the record, which was held by another phenom: LeBron James.
James' 37 points on Dec. 13, 2003, were the most by an 18-year-old in a game in league history, until Flagg's performance against the Jazz. With 42 points, Flagg rewrote the record books, also becoming the first 18-year-old to drop 40-plus points in a game.
Already, the leaderboard for single-game points by an 18-year-old is dominated by Flagg and James. According to StatMuse, those two players take up the top 14 spots on the all-time list, followed by Dwight Howard and Kobe Bryant, who each dropped 24 points as an 18-year-old.
Here's are the 10 highest-scoring games by an 18-year-old in NBA history, per StatMuse.
Rank Player Team Age Date Points
1 Cooper Flagg Mavericks 18 years, 359 days Dec. 15, 2025 42
2 LeBron James Cavaliers 18 years, 348 days Dec. 13, 2003 37
3 LeBron James Cavaliers 18 years, 354 days Dec. 19, 2003 36
4 Cooper Flagg Mavericks 18 years, 343 days Nov. 29, 2025 35
5 LeBron James Cavaliers 18 years, 360 days Dec. 25, 2003 34
6 LeBron James Cavaliers 18 years, 334 days Nov. 29, 2003 33
7 LeBron James Cavaliers 18 years, 363 days Dec. 28, 2003 32
LeBron James Cavaliers 18 years, 355 days Dec. 20, 2003 32
9 Cooper Flagg Mavericks 18 years, 335 days Nov. 21, 2025 29
10 LeBron James Cavaliers 18 years, 325 days Nov. 19, 2003 28