The man who helped formulate the mechanics of Klay Thompson‘s jumper has every right to call himself a shot doctor. That’s because he is, literally, a doctor. A neonatal intensive care specialist, to be specific.

Dr. Joseph Kaempf claims he was “nothing special, in terms of an athlete.” His playing career never moved past high school. But when he and his wife had four boys and one girl he started coaching their kids’ sports teams. Klay Thompson happened to play on a middle school-age team with Kaempf’s youngest son in Portland, Oregon, where Thompson’s father, Mychal, lived for the majority of his NBA career.

That was the genesis of a jump shot that made Klay Thompson a first-round NBA draft pick by the Golden State Warriors, where he joined Stephen Curry to make what former Warriors coach Mark Jackson dubbed the best-shooting backcourt ever. The jump shot got him a spot on the 2014 Team USA world championship basketball team. It helped him earn a $69 million contract extension from the Warriors. It got him a trip to New York for the All-Star Game and a place in what’s become the most anticipated 3-point shootout in the 29-year history of the event.

“Whose shooting form do I admire? Klay Thompson,” said Los Angeles Clippers guard J.J. Redick, another member of the eight-man field. “There’s not a lot of extra movement.”

Said Warriors coach Steve Kerr, the NBA’s all-time leader in 3-point shooting percentage: “From a technical standpoint, I think Klay is as good as anybody I’ve ever seen.”

You can trace it back to the teachings of the neonatal doctor.

“I credit a lot of my shooting ability to Dr. Kaempf,” Thompson said. “He did a great job with me when I was young.”

Kaempf doesn’t really want to get the assist.

“The local grocer could have coached him and he would’ve been great,” Kaempf said in a recent phone conversation.

Kaempf feels it would be just as outrageous to take credit for the NFL quarterbacking success of a kid he coached in baseball: Aaron Rodgers. To Kaempf, it isn’t what he taught Thompson, it’s what Thompson was able to do with the knowledge.

“My son Joey has the same shot,” Kaempf said. “He just, unfortunately, has a 5-foot-11 dad.”

Klay, of course, has a 6-foot-10 former No. 1 overall NBA draft pick for a dad. He also has a collegiate volleyball player for a mom. Klay grew to be 6-7, and his height makes his shot difficult for guards to contest.

Mychal Thompson played when big men stayed near the basket and didn’t fancy themselves 3-point shooters. The elder Thompson took only 12 3-point attempts (and made one) in his 12-year NBA career. So Klay’s shooting form wasn’t exactly inherited.

Kaempf says he actually sees more of Julie Thompson, Klay’s mother, in Klay.

“When I coached him, he never complained, never called attention to himself,” Kaempf said. “Never said, ‘My dad’s an NBA athlete.’ But he was competitive and driven.”

Theirs wasn’t a star-studded team that traveled the nation. They played around Oregon, with an occasional trip up to Seattle. Kaempf rotated his lineups to give everyone a shot at playing time.

“He didn’t start every game — although he should have, by every objective measure,” Kaempf said. “Klay never had an issue with that. He is the most modest young man. He never called attention to himself.”

Kaempf stressed proper technique at close range. He focused on getting the ball up above the forehead, extending the arms and keeping the hand spread, with the index and middle fingers making a “V.”

“Before every day in practice, we would shoot our jump shot over our head from just inside the key,” Thompson said. “And I swear that helped me develop my form. I kind of grew into my shot from that.”

“I would say, ‘Shoot with good form close in and move out,'” Kaempf said. “Don’t shoot with bad form at 20 feet, shoot with good form at 3 feet.”

Kaempf studied the shooting forms of Jerry West, Pete Maravich, Geoff Petrie and Dell Curry for examples of proper technique.

Curry — yes, the father of Steph, Thompson’s backcourt partner — said he imparted his shooting knowledge to his sons by bringing them to basketball camps he appeared at around the country during his playing days.

“In kind of a sly way, I was talking and teaching them the fundamental forms of shooting,” Dell Curry said. “They were not really realizing I was talking specifically to them. The only thing I was really working on was the ability of [getting it] from his waist to shooting it above his head.”

And in that emphasis can be found the main difference in Stephen Curry’s and Klay Thompson’s shots. Curry’s shot is seemingly produced by his entire body, while Thompson’s relies more on his arms. Since Curry’s shot starts lower it goes up higher … and makes a more noticeable entry through the net. Curry puts most of the splash into the Splash Brothers.

“I think Steph is more rhythm-based,” Kerr said. “He likes to dribble into his shot. Klay can do that too, [but] he’s probably more comfortable than Steph just catching and shooting.”

Curry talks about how, with Thompson’s shot, “it gets into his pocket.”

“He gets into the shooting pocket kinda quick, as opposed to that fluid motion from bottom to top,” Curry said.

“He gets it here [up to his head] and once he gets it here, it’s over. I kind of am fluid from the time I bring it up to the shooting pocket and all the way through. Both work, obviously.”

Obviously. Curry leads the league with 3.2 3-point field goals made per game. Thompson is sixth in the NBA in 3-point percentage at 44 percent.

They’ll take on Redick, Kyle Korver, Kyrie Irving, Wesley Matthews, James Harden and defending champ Marco Belinelli in this year’s 3-point shootout. You can make a case for any of them to win it, which is why this has turned into the must-watch event of All-Star Saturday. But the unofficial champion of shooting technique is Thompson.

“From the shoulders up, it’s textbook,” said Kerr, who won the contest in 1997. “It’s so easy, from deep range.” Redick marvels: “His ability to get his shot off, no matter where he catches the ball — down, up high, whatever — it’s right into that shot pocket.”

It all goes back to the gym at St. Thomas More school in Portland, and the doctor who just wanted to help his sons and their teammates get better at basketball. “If I played a small role at most, I’m very happy about that,” Kaempf said. “He deserves all the credit.”