In 1994, he cold-called the Golden State Warriors, the NBA’s worst free-throw-shooting team during the 1993-’94 season. The operator declined to put him through to head coach Don Nelson (Donnie’s father), he says, but Boren managed to connect with assistant coach Gregg Popovich (who since has coached the San Antonio Spurs to four NBA titles).

At Popovich’s request, Boren sent his résumé, which he says included a letter of recommendation from Denny Price, Boren’s college buddy. At the time, Price coached at Phillips University in Oklahoma, and his son Mark was on his way to becoming one of the NBA’s career leaders in free-throw percentage (.904). A few days later, Popovich told Boren to go to the airport and pick up a plane ticket to Milwaukee, where the Warriors were playing the Bucks the following night.

“I thought I was going for an interview, so I took enough clothes for one day,” says Boren. Upon arrival at the team’s hotel, he walked the coaches through a three-hour tutorial that lasted until 1 a.m. Boren remembers Don Nelson ended the meeting by saying, “All right, you’re hired. But if it doesn’t work, you’re fired.”

The next thing Boren knew, he was on a 10-day NBA road trip and in desperate need of a change of clothes. His flexible work schedule allowed him to fly to games the rest of the season, and Boren eventually followed Don on the coaching carousel to the New York Knicks and then Dallas.

In 2005, Don stepped down as Mavericks coach and was replaced by Avery Johnson. Johnson retained Boren and when Johnson was fired in 2008, new coach Rick Carlisle also kept Boren on the staff. Boren has an office near the locker room and received a championship ring after the Mavericks won the 2010-’11 title.

Like many instructors, Boren says he’s a better coach than he is a shooter, describing himself as “good but not great” at the line. “Today I made 95 out of 100; yesterday 94 out of 100,” he says, then admits: “I have only made 100 straight one time.”

John Wooden, the legendary coach at UCLA, holds the record for most consecutive free throws made by a professional. As a member of the Indianapolis Kautskys, a team that played independently and in several leagues during the 1930s, Wooden nailed 138 consecutive free throws during one stretch. And he shot them underhanded, which is also known as “granny style.”

“From a physics standpoint, it is the best way to shoot,” Boren says. “The ball is ­released farther in front of your body, therefore the peak of the arc is closer to the basket and the size of the target is larger.” He is quick to make a point, however, that granny style is not stylish enough for players. “Players [today] won’t accept teaching that includes granny style,” he says, “so why try?” 

MATT MCCUE is a writer living in New York. He is the author of An Honorable Run and has contributed to ESPN The Magazine, The Wall Street Journal and New York magazine. When he was a boy, his mother always told him “free throws win ballgames.” He can still hear her voice.