SALT LAKE CITY – Cooper Flagg sat in front of his locker with his left ankle heavily wrapped in ice, still feeling the bittersweet emotions that came from his first 40-point game in the NBA.

The youngest player in the league persevered through pain and finished with a career-high 42 points in Monday’s overtime loss to the Utah Jazz, while tying a franchise record for the most points scored by a Mavericks rookie.

The final box score will tell the story of the most points ever scored by an 18-year-old in the Association’s 80-year history, shattering a record once held by LeBron James. What it won’t say is how disappointed Flagg was to reach an unprecedented milestone in a loss – the only statistic that matters to him.

“It’s tough,” Flagg said. “I want to look at it [in] wins and losses. Obviously, we didn’t win. It’s tough for me to want to be happy, but obviously it’s a success and we’re going to try to keep getting better from here.”

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It was just 44 years ago on Nov. 14, 1981 when Mark Aguirre, the Mavericks’ only other No. 1 overall pick, set the single-game record for the most points scored by a rookie in team history. Flagg, just as he did on draft night, followed Aguirre’s footsteps yet again when he matched the total in overtime with a pair of free throws. He also used the stripe to reach 40 points during the final seconds of regulation.

Flagg’s pursuit of 40 appeared to be in jeopardy when he rolled his left ankle shortly before Jazz guard Isaiah Collier fouled him with 4.5 seconds left in regulation. The Mavericks rookie hobbled around the court until he realized he had to go to the free throw line to remain in the game. Despite the pain, he sank the first free throw.

“It was hurting, but I wanted to stay in the game no matter what,” Flagg said. “I’m not coming out or anything like that. Just playing through it, being tough and knowing it’s a key moment in the game.”

Flagg has built a reputation for being a competitor through every level of his basketball career. His 42-point night also matched his career high from his lone season at Duke, but that game against Notre Dame on Jan. 11 resulted in a win.

Though he put the Mavericks in position to leave Utah with a victory, Flagg couldn’t help but accept accountability for mistakes he made during the fourth quarter. He had two of his four turnovers on back-to-back plays that led to a brief trip to the bench.

“I gotta be better,” Flagg said. “I threw a couple of dumb turnovers and missed a couple of easy ones. Just gotta be better executing down the stretch like that and we gotta get good looks on each possession.”

Those mistakes were costly, but they were anomalies compared to his masterclass performance during the first 36 minutes of action. Flagg was decisive and intent on getting downhill against the Jazz’s interior defense led by Lauri Markkanen and Kyle Filipowski. He drove to the basket throughout the game and finished with his dominant right hand, but also connected on several contested layups with his left.

Flagg also sprinkled in his signature midrange jumper, which Jazz coach Will Hardy praised during his pregame news conference.

“I know that you start talking about midrange and some people get uncomfortable,” Hardy said. “But when you watch the end of close games, when you watch the playoffs, those shots are so necessary.”

It took encouragement from his coaches and teammates, but Flagg has learned to embrace moments when his team needs him to be aggressive offensively. He reached his former career high of 35 points on Nov. 29 when Anthony Davis and P.J. Washington missed a win over the LA Clippers. Without Davis in the lineup Monday, Flagg reached new scoring heights yet again.

“It doesn’t surprise me at all,” said Washington, who had a double-double of 25 points and 13 rebounds. “I know exactly what he’s capable of. He’s a special player. It’ll be a lot more to come, obviously, and we know that.”

Coming off the best game of his NBA career, Flagg nearly deferred to Washington to receive the first postgame interview, but the seventh-year veteran had to remind his rookie of what he’d just accomplished.

“Bro, you just had a career high,” Washington quipped, urging Flagg to relish the moment despite the undesirable circumstances.

Flagg is the fourth teenager in NBA history to record at least 40 points and five assists in a game, joining Anthony Edwards, Kevin Durant and James.

Only 56 days into his rookie season, Flagg has become the youngest player in NBA history to record at least 10 assists in a game and the youngest to score 40 points. Not to mention, he just earned his first piece of hardware with the Western Conference Rookie of the Month trophy for games played in October and November.

Those are notable individual accolades to Flagg, but it’s never been about that.

“I’m not really focused on a lot of that stuff,” he said. “I’m more just focused on being present day-to-day and trying to get better and get as many wins as we can.”

A mature response from Flagg, who doesn’t turn 19 until Sunday.

It depends on health, but he has two games left to put the finishing touches on one of the most remarkable resumes in NBA history for an 18-year-old.

X/Twitter: @MikeACurtis2

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