SACRAMENTO, Calif. -- As fiery a competitor as Luka Doncic is, he couldn't stop smiling after the Dallas Mavericks' 133-128 overtime loss Saturday night to the Sacramento Kings.

That's how much Doncic enjoyed playing with new teammate Kyrie Irving for the first time -- and how excited Doncic is about the possibilities for the All-Star backcourt partnership.

"It's only our first game together, but it's so fun to play with this guy," Doncic said. "He's an amazing basketball player, and I think it's going to be really fun. First game, it was really fun."

Doncic had 27 points, nine rebounds and five assists in his return after missing four games due to a right heel contusion. Irving, who was playing his third game for Dallas since being acquired in a blockbuster trade with the Brooklyn Nets, had 27 points, seven rebounds and seven assists.

But it was another All-Star guard who stole the spotlight down the stretch. Sacramento's De'Aaron Fox, who will make his first All-Star appearance after being selected as an injury replacement, continued his trend of clutch dominance by scoring 26 of his game-high 36 points in the fourth quarter and overtime.

The Mavs, however, were encouraged by the first glimpse of Doncic playing alongside his new superstar sidekick.

"For the first time for those guys to play minutes together, I thought it was really, really good," Dallas coach Jason Kidd said. "It was just natural, nothing forced. I thought this was a great game for us, as much as we'd like to be on the winning side."

Doncic acknowledged that he was fatigued in the fourth quarter and overtime coming off an extended absence. He was held scoreless in the fourth quarter, and his only basket in overtime was a layup with five seconds remaining that the Kings didn't mind surrendering.

Doncic regretted taking a potential game-tying 3-pointer on the previous possession, saying he should have passed the ball back to Irving instead of settling for a contested stepback. Irving had carried the Mavs' offense late in the game, scoring 16 points in the fourth quarter and overtime, including a sidestep 3 just seconds earlier.

"It's my bad," Doncic said. "Should have gave it back to Ky. For me, it's still a learning process. But for sure, I should have gave it back. He was really hot down the stretch, so that was on me for sure."

Irving, however, took no issue with Doncic's shot selection in that instance.

"Either way, it was going to be a great shot, him shooting it or me shooting it," Irving said. "No pressure in terms of 'give me the ball' in that situation if he feels confident enough to take the shot. ... If he would have passed it to me, it may be a different result, maybe not. But the what-ifs don't matter."

Doncic, who quickly signed off on the Irving trade when the Mavs' front office sought his input, is eager to adapt to playing alongside an All-Star for the first time in his career. Irving has significant experience playing with other superstars, such as LeBron James with the Cleveland Cavaliers and Kevin Durant with the Brooklyn Nets.

"The biggest asset I have is just being able to be fluid out there and adapt to any situation that they throw me in role-wise," Irving said. "Point guard, playing on the ball, I've played with guys who have really been ball dominant. So it's nothing new, but I think it's just a figuring-out process that takes time."