Veteran outfielder Darnell McDonald calls him “King James.” As in LeBron James. As in the former hoops prodigy turned NBA legend.

So, to the Chicago Cubs official who asked me with a smile, “Don’t crank up the hype machine too far,” I can offer only one possible response:

Your own players are doing the cranking!

“He’s legit, a physical specimen, impressive bat speed — and a rocket arm, too,” outfielder Scott Hairston says.

And left fielder Alfonso Soriano, who knows something about phenoms — remember his two homers and MVP performance in the 1999 Futures Game at Fenway Park? — sounds equally excited.

“He’s going to be something,” Soriano says.

The player in question, outfielder Jorge Soler, turns 21 on Monday. Recently, club president Theo Epstein said to one of the Cubs’ veterans, “Not bad for a 20-year-old, huh?”

“Twenty?” the player replied. “I thought he was 25!”

Soler looks the part at 6-foot-4 and 215 pounds. The surprising thing is, he acts the part, too, displaying uncommon maturity — not just with his offensive approach, but also his defense and baserunning.

We’re talking about a kid who didn’t play a game between the 2010 World Junior Championships and his debut in the Cubs’ system last summer, a gap of approximately two years.

During that time, Soler defected from Cuba, established residency in Haiti and received clearance from the US Treasury Department’s Office of Foreign Assets Control, enabling him to sign with a major-league club.

The Cubs went all-in on him, eager to land a major foreign talent before new restrictions on international spending took effect. Their winning bid for Soler — $30 million over nine years — was a record for a 20-year-old.

At the time, the Cubs had seen Soler only at junior international tournaments and at their own academy in the Dominican Republic. But if Soler, a right-handed hitter, becomes the next Giancarlo Stanton, the deal actually could prove a bargain. A major bargain.