Jason went to both law and business school and was obsessively entrepreneurial. He loved selling and schmoozing with customers on a noon-to-midnight instead of 9-to-5 clock. Visiting casinos, he crisscrossed the country in an aging Chrysler Concorde, often with Skoal tobacco packed in his lip. He had come from tobacco users; his dad had smoked cigars, his mom cigarettes since age 14.

It was unseasonably warm on May 10 when Jason, driving back to Las Vegas from Arizona, felt his throat tickle and his head hurt. His legs had felt heavy for several months. Several days later, he attacked the symptoms with a homegrown remedy: He downed most of a 12-pack of Bud Light Chelada.

“It didn’t work out too well,” he said with a laugh, looking back. He felt worse in the morning.

My first memories of Jason come from the dugout. We were teammates for years in Little League. I was a two-bit player and Jason a perennial All-Star — center fielder and shortstop, leadoff hitter. He had the same gifts in football and basketball. Not just that — he was funny, self-effacing, a good student and a good guy. His junior high nickname was Golden.

But all was not golden for Jason. One morning in eighth grade, our friend Tom Meier found him in the locker room, sobbing. Jason had learned the day before that his dad, Joel, at 46, had been told he had colon cancer.

“Here was the strongest person I knew, and he was absolutely shattered,” Tom said.

Over the years, Jason’s friends and family would debate the extent to which his father’s cancer and eventual death, in the summer before our senior year of high school, unmoored Jason. He had been Jason’s first coach and chief advocate, attending every game, often chomping a stogie, stoic and hunch-shouldered. In the weeks before he died, he watched Jason, a 5-foot-9 point guard, help lead Boulder High School to a state basketball championship game.

After his father’s death, Jason’s senior-year grades tanked such that he had to explain them to Occidental College, where he was to play basketball and baseball. A manic side of Jason became more prominent. He never settled down with a family, and his businesses came and went. His inimitable passion remained, while his follow-through sometimes faltered.

“Dad was his guru; I don’t know how to describe it,” Guy Greenstein, Jason’s older brother, and one of five siblings, told me. “When my dad was gone, he was left to flounder a bit.”