A former first-round Draft pick with a 100-mph fastball, Jeffress was hit with a second suspension for marijuana use in 2009, banned for 100 games and sent home to Virginia. Jeffress felt empty there, so he left and traveled alone to Florida, where he took a job bussing tables at a pizzeria chain.
"I literally felt like nobody cared," Jeffress said. "I didn't even feel like my own family cared. Now, that was all in [my head], but I felt like, 'I don't belong here.' So I left after two weeks. I should have stayed at home, but I left and got a job. I was 21, 22 years old, and I was still a fool.
"I was working that job, and I thought, 'Is this really where I want to be? Is this really what I want to do? Do I really want to be working right here?' That's what really changed things for me. I don't care who knows about it now, because it made me a better person.
"It showed me what I want to do with my life."
What Jeffress wanted to do was pitch.
Nearly seven years later, Jeffress is pitching some of the Brewers' biggest innings. With left-hander Will Smith on the disabled list, Jeffress has sole possession of Milwaukee's closer role, and he has gone 3-for-3 in save chances through four scoreless appearances.
"It's probably the highest point of my career, watching him do what he's doing," said Jeffress' agent, Joshua Kusnick.
After his stint bussing tables, Jeffress rededicated himself to baseball. The Brewers moved the right-hander to the bullpen when his suspension expired in mid-2010, at least partially in the hope that everyday duty might sharpen Jeffress' focus.
Jeffress pitched well enough to make it back to the Majors by year's end.
"Man, when I got to the big leagues ..." Jeffress said, his voice trailing off and his eyes looking skyward. "I can't even describe it. I knew that's where I was supposed to be. My mind was getting stronger. I knew it, I felt it -- everybody saw it."
But more challenge lay ahead.
Traded to Kansas City in the Zack Greinke deal, Jeffress never gained a foothold with the Royals and was dealt to Toronto for cash after parts of two seasons, during which he posted a 5.65 ERA. Jeffress was suffering seizures, especially when he wasn't smoking marijuana, and he finally found a solution when the Blue Jays sent him to Buffalo to see a specialist. Jeffress, doctors discovered, had long suffered from juvenile epilepsy.
Jeffress' seizures have been under control since then, but his tenure with Toronto ended after three poor outings early in 2010. He was designated for assignment.
A free agent for the first time, Jeffress and Kusnick could choose where the reliever would go next.
"One club offered me a Major League deal for Jeremy," Kusnick said. "The Brewers offered us the biggest Minor League deal that was offered to us, but I legitimately had a big league deal on the table.
"I said, 'Jeremy, we have a crossroads here. Do we take the big league deal and try to fix it on the fly in the big leagues, or do we go somewhere you can anchor yourself and right the ship permanently?'
"I told him, 'If I'm wrong, you can fire me.' I thought the situation in Milwaukee could fix him permanently. It's probably the smartest thing I've ever done."
Again, Jeffress earned his way back to the Major Leagues. The Brewers promoted him in the final week of July 2014, and he has been in the Majors since. Including his career-high 72 appearances last season, and four scoreless frames to open 2016, Jeffress has a 2.60 ERA in his second stint with Milwaukee.
"This road has been long, I'm telling you," Jeffress said.
Today, the pizzeria where Jeffress once worked is one of his favorite restaurants.
"I know a lot of people say that those suspensions were bad, but I look at it as a good thing. I really do," Jeffress said. "No. 1, it saved my bullets. No. 2, it made me a better person. It made me see what I really want to do in life."
Adam McCalvy is a reporter for MLB.com. Follow him on Twitter @AdamMcCalvy, like him on Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.