When Rockets coach Mike D’Antoni praises James Harden, a task that comes up from time to time, he will often say, “You can’t speed him up.” That means more than Harden will walk the ball up the court and look things over.

Harden demonstrates that quality so regularly it is often overshadowed by long step-back 3s and rapid-fire crossover dribbles. But when players say that as veterans the game slows down, Harden’s game is the embodiment of being able to control things as if even opponents are on a string at his command.

It is a rare quality, rarer still and perhaps unheard of for a player not yet old enough to order a beer.

With Mavericks guard Luka Doncic collecting triple-doubles at Russell Westbrook levels — with a league-high seven this season, he is just three-tenths of an assist per game shy of averaging a triple-double — he might seem more like Harden’s backcourt partner. Doncic (29.9 points, 10.4 rebounds, 9.7 assists) would seem to have a great shot to join Westbrook and Oscar Robertson in the exclusive club of players to average double-digit points, rebounds and assists.

Westbrook, however, becomes a fiery blur. Doncic dominates more like Robertson and Harden, at a cool and calculating pace, as in control as a conductor commanding an orchestra.

You can’t speed them up, either. But conductors operate without opposition, with Harden and Doncic seemingly able to control their opponents, too.

“That means he will take you at his pace, (so) he’s going around you at his speed,” D’Antoni said. “He’s not going to be out of control. He’ll get (to) you and lull you. He’s so strong. James and Doncic are the same way. They can just play at their speed (like) Steve Nash. Special players, they play at their speed, whatever that is.”

With Harden, there is a bullish strength that first draws and then powers through contact. With Doncic, there is the size of a 6-7 ballhandler, allowing him to see over defenders and deliver passes as he chooses. That has drawn comparisons to LeBron James, but with the added weapon of a Harden-esque step-back 3-pointer.

“It’s strength more than anything,” D’Antoni said of Doncic’s physical advantage. “He’s probably stronger than you think. He’s got a big body.”

Doncic is on a roll coming into Sunday’s matinee with the Rockets comparable to Harden and James runs.

He became just the fifth player to average a 30-point triple-double over a 10-game stretch. On Nov. 1 Doncic memorably dueled James, his role model, and the comparisons became inevitable, though Doncic plays with more polish than James did when he too began his NBA career as a teenager.

Only James is averaging more assists than Doncic’s 9.4 game, or more potential assists than his 18.4 or more points created off his passes than his 23.7. Doncic, however, won’t turn 21 until February. His 15 triple-doubles before 21 top Magic Johnson’s seven for the most all-time. He has six 30-point triple-doubles. James had two.

“You never know who you can inspire along your path,” James said after the Mavericks’ game in Los Angeles, won by the Lakers in overtime. “For me, playing the game the right way, getting my teammates involved and playing for the purity of the game, I was able to inspire a kid that wasn’t even in America. That’s pretty special.”

Only Doncic and James are averaging 25 points, 7.5 assists and 7.5 rebounds. Only Michael Jordan, Larry Bird, Harden, Westbrook, James and Robertson have averaged those numbers for a full season.

“He was already a great player last year, borderline All-Star,” Warriors coach Steve Kerr told the media in Dallas on Wednesday. “He’s for sure an All-Star this year. He just looks like he knows he’s the best player on the floor out there.”

That’s not hyperbole. Though there is a long way to go, Doncic’s run has pushed his true shooting percentage, which considers the value of 3-pointers, past Harden’s for the league best at .632, according to basketball-reference.com. Harden sits right behind at .627. Both top Harden’s 2017-18 league record of .619.

“He’s having a phenomenal year,” Mavericks coach Rick Carlisle said in Dallas on Wednesday. “I don’t know how else to characterize it. His ability to balance the paint game with the outside game makes him really tough to deal with for opponents, and he’s on a really great roll right now.”

One that has put Doncic in the middle of the early MVP conversations, and in fast company by doing things at his own pace.

“They’re just special players,” D’Antoni said. “Very honestly, it’s hard to explain. It’s hard to explain something special. (It’s a) talent. Why is the best actor the way he is? It’s a talent. It’s an X-factor you can’t explain. You can’t coach it. Some people have it; some don’t. James, Doncic, those guys have it.”

jonathan.feigen@chron.com

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