Doncic, the Mavericks' 19-year-old rookie sensation from Slovenia who was drafted No. 3 overall this past summer, patiently waited in the hallway not far from the locker room entrance for several moments until a team official emerged with a signed jersey from LeBron James.
Doncic beamed a wide smile with James' game-worn jersey in hand as he headed back to the visitors locker room, following his 14-point, seven-assist, five-rebound performance.
"I always wanted his jersey," Doncic said afterward, with James' jersey sitting in his locker. "It was something special to me."
It was also their first matchup against each other. Doncic said they arranged the exchange during the game. James wrote on the jersey, in part, "Strive For Greatness."
Speaking of his first matchup with his idol James, Doncic said, "It's very special. I was waiting for this game, and it was very special to me."
James finished with 29 points, six assists, five rebounds, three steals and hit the game-winning free throw with 2.1 seconds left.
James said he isn't surprised that Doncic has been able to thrive in the NBA at such a young age.
"I think European players are developed faster than NBA guys, meaning American players," James said. "I think he's been in a pro development stage now for how many years? Since he's 15? So I don't think this is intimidating to him. I don't think this game is something he hasn't seen before.
"I think that's the best thing about European basketball, pro basketball over there. They develop their players so early."
ESPN's Dave McMenamin contributed to this report.