"Absolutely, that passed through my mind," Quintana said through a translator, White Sox coach Lino Diaz. "I had four months where I was out of baseball, and I totally thought I was done. But I had really good people around me, especially my family, who supported me throughout all this."
After joining the Mets as a free agent on April 26, 2006, the native of Colombia tested positive in October of that year. Quintana admits now that his first reaction was to think the positive test was some sort of bad joke because he wasn't taking anything.
It was medicine that Quintana had been given for a back issue that caused the positive, according to the pitcher.
"I feel like it was lack of orientation more than anything," Quintana said "I was just taking medicine. I wasn't trying to get anything else. I was going to a gym where they had a sports medicine guy.
"So back then, I asked, 'Hey, I need something for my back -- but just something that is not going to be against what I'm doing.' And unfortunately, that came out."
One mistake did not erase Quintana's big league chances, as the Yankees signed him as a free agent on March 10, 2008. The White Sox picked up the lefty after he departed the Yankees in 2011, and he has since become a rotation mainstay.
That long chain of events culminated with Quintana facing the Yankees in Alex Rodriguez's return to action on Monday night. Quintana earned the victory, improving to 6-3 with a 3.51 ERA and 110 strikeouts over 138 1/3 innings. He's also 2-0 in his career against the team that kept his dream alive.
"I'll always be thankful to the Yankees for giving me that opportunity," Quintana said. "I learned a lot from that experience, and that's what's important to me now.
"I'm sure they don't really want to cause any harm or anything like that," added Quintana of those players who test positive. "You just have to be careful."
Scott Merkin is a reporter for MLB.com. Read his blog, Merk's Works, and follow him on Twitter @scottmerkin. This story was not subject to the approval of Major League Baseball or its clubs.