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Jaycob Brugman lined a ball into the gap sometime last Monday afternoon at the Oakland A's spring training facility during the A's extended spring training game against the Cubs. He rounded first base hard, but the outfielder cut the ball off and he thought better of going for second and made his way back.

He started taking off his batting gloves to hand them to the first-base coach, a short guy about 5'9" and maybe 160 pounds. The coach had shaggy brown hair and a goatee that didn't quite connect, which made him look a little like a pirate. Captain Morgan, the guys called him, or The Count of Monte Cristo.

"So," Casey Thomas said, giving Brugman a stern look but taking on an exaggerated laid-back surfer drawl, "you really did get slower since high school, huh?"

Then Thomas, a rookie shortstop playing the role of first-base coach with full commitment, grinned, and Brugman threw his batting gloves at him. Thomas called Brugman a jive turkey, and they both laughed.

A few hours later, when everyone was going home, Casey was tired; they all were tired. It had been a long day: They'd gotten to the park at close to 6 a.m. and now it was creeping on 4 p.m., and much of that time was spent outside in the Phoenix heat. But Casey was still making people laugh, smiling and happy to be a baseball player and looking healthy as ever.

Later that night, Brugman got a phone call.

Casey was dead.

CASEY THOMAS WAS 24 years old and just starting his pro baseball career, a shortstop in his first full year in the Oakland A's farm system.

What happened, exactly, nobody will know until the autopsy results come in a few weeks. From what people who know the family have heard, it doesn't sound like drugs or foul play or anything of the sort—almost worse, it seems like a random stroke of horrific chance.

Thomas lived in Phoenix with his parents. He'd grown up there. When he left the facility, he went to his mom, Kristy's, house to go swimming. They spoke on the phone that afternoon; she was on her way home from California with his stepdad.

When she arrived home early that evening, Casey was on the floor of their bathroom. It looked like he'd just passed out. He was still wet from swimming.

Best guess anyone has so far is an unknown medical condition, or maybe something to do with the searing temperature.

"Just a weird natural thing," says Mitch Sokol, a veteran scout and a close Thomas family friend, echoing what several folks told B/R Mag. "Maybe an aneurysm, maybe a heart thing, maybe it's heat related. Some of these young kids have to sit there and work in this heat and play all summer long, and it gets really tough. But to be honest, I don't know. Nobody knows."

Teammates say he seemed fine all day at the field and even when he left. Brugman says, "I don't remember what it was exactly now, but he had us going—I was laughing really hard."

The A's declined to comment beyond a brief statement in which Oakland executive vice president of baseball operations Billy Beane said all the appropriate and expected things, that they were "devastated" and calling Thomas "a wonderful young man and teammate" who "will be missed by all in the A's organization."

This sucks for all the obvious reasons—because he was so young; because there's no clear reason yet; because if it truly was a random act of death, then what does that mean for everyone else?—but for those who knew Thomas, there's a clear level or two of extra heartache.

Casey was the kid you weren't sure could make it but were thrilled when he did. The underdog who gives everyone else hope.

And by all accounts, Casey Thomas was the kind of ballplayer who, from his first days playing baseball to his last day on Earth, reminded people what baseball is all about—what sports are all about, and maybe even what life is all about.

ONE OF CASEY'S FAVORITE mottos was "own your flow," inspired by the long hair his coaches were always trying to make him cut—and a good way to sum up his general approach to life.

Thomas' back-and-forth with Brugman while coaching first base on the last day of his life was how he spent most of his days, or at least his favorite ones: on a baseball field, doing baseball things, making teammates laugh. "Everyone in the Oakland A's organization loved him,"