Dallas Mavericks head coach Rick Carlisle says Mavs star Luka Doncic is “working his butt off” this summer in terms of getting stronger.

Doncic, who won the 2019 Rookie of the Year Award, is going to have people coming at him next season — according to Carlisle — so the Mavs' floor general has to be prepared for that.

“It’s just a natural progression that every player needs to have going from Year 1 to Year 2, especially someone like Luka that had such a great first year,” Carlisle told The Dallas Morning News. “People are really going to be coming for him in his second year, and the continued work on body and conditioning and developing his game is going to keep moving him in the direction of becoming a really great player.

“I know he’s working his butt off this summer. I know he’s very motivated for this season.”

Luka Doncic put on a show from start to finish last season. The 20-year-old averaged 21.2 points, 7.8 rebounds and 6.0 assists while shooting 42.7 percent from the field, 32.7 percent from beyond the arc and 71.3 percent from the free-throw line.

Doncic recorded 24 double-doubles and eight triple-doubles. The Mavs' new franchise player led all rookies in points per game and was second in assists per game.

The Mavs can't for next season, as they will have All-Star power forward Kristaps Porzingis on the floor next to Doncic. Dallas envisions Porzingis and Doncic being a lethal pick-and-roll/pop duo for the next decade.