SALT LAKE CITY -- Cooper Flagg scored the most points by an 18-year-old in NBA history, but he couldn't enjoy the accomplishment because it came in defeat.
Flagg put up 42 points -- topping the previous mark of 37 set by LeBron James on Dec. 13, 2003 -- in a 140-133 loss to the Utah Jazz on Monday night.
"Obviously, we didn't win. So, it's tough for me to want to be happy or any of that," said Flagg, who had a bag of ice on an ankle after rolling it at the end of regulation. "But obviously, it's a success."
Flagg, who will turn 19 on Sunday, also registered 7 rebounds, 6 assists, 2 blocks and a steal in an early career performance from the No. 1 pick. The rookie forward is the third teenager in NBA history with at least 40 points, 5 rebounds and 5 assists, joining Kevin Durant and James.
"The more time he spends on the floor, the more he sees, the better he gets. He displayed it all tonight," Dallas coach Jason Kidd said.
Flagg has been playing his best basketball in recent weeks, averaging 25.7 points across the past seven games. His aggressive play has gotten him to the foul line, where he went 15-for-20 against Utah.
"It's come a long way from the start of the season, so I'm proud of that fourth quarter," Flagg said. "It's a new game ... but I am getting more and more comfortable ... and just settling in, honestly, just being myself and letting the game come to me."
He tallied 12 points in the fourth and made a savvy play to send the game into overtime when he missed a free throw on purpose with such a big carom that teammate Max Christie got the rebound with 3.9 seconds remaining and was fouled.
With big man Anthony Davis out and Dallas missing several other teammates to injuries, Monday's game might be a harbinger of things to come as Flagg becomes a centerpiece of the Mavericks' offense.
"We were going to Coop. He was killing them the whole game, so they finally tried to double him," Dallas forward P.J. Washington said. "It doesn't surprise me at all. I know exactly what he's capable of. He's a special player, so there will be a lot more to come."
Flagg also tied Mark Aguirre for the most points by a rookie in Mavs history as he begins to make his mark on the franchise. But Flagg couldn't stop thinking of what he could have done to get the win despite the throbbing ankle. The Jazz made a late 11-0 run then dominated in overtime as Flagg didn't score a basket in the extra period.
"I got to be better. I had a couple of dumb turnovers, missed a couple easy ones, but I got to be better, executing down the stretch like that," Flagg said.
Setting records might be nice, but Flagg said it means he's consistently improving, and that's been his goal all season.
"I'm not really focused on a lot of that stuff [the records]. I'm more just focused on being present, day to day, and trying to get better and getting our team as many wins as we can," he said.
The Associated Press and ESPN Research contributed to this report.
