The test showed otherwise.
About a month after Katin took the test, he got a call from someone on the Huntsville staff, asking if there were any reason the outfielder would have tested positive for steroids.
The phone call -- and the accusation -- shocked Katin.
"It was jaw dropping," Katin said Tuesday in a phone interview. "It was completely out of the blue. Things are going through your mind -- what could've possibly done this? -- and luckily for me, it all worked out in the end."
Katin, 28, was told he would be suspended for 50 games, and he appealed the findings. Two months after he got that phone call the suspension was overturned, making him the only ballplayer who has successfully appealed. Katin is hoping his former University of Miami teammate, Ryan Braun, will be the second.
In Katin's case, his first sample came back with a high level of testosterone.
"They assumed I was on something," he said.
In 2007 in the Minor Leagues, players would submit two urine samples -- marked "A" and "B." Katin was notified that he tested positive for high levels of testosterone, and he said the "B" sample was then tested for synthetic drugs. It came back negative. Now, if a player has a high level, Major League Baseball will automatically test for synthetic drugs before contacting the player.
"If I hadn't appealed, I imagine they would have never tested me for actual synthetic steroids," Katin said. "It would've been a positive for my high levels of testosterone. They come at you like that, and if I was actually using something, I would've said, 'OK, I got caught.' But since I wasn't using anything, I appealed."
Katin's agent filed the appeal, and the samples were tested for performance-enhancing drugs. None turned up. But it took two months before Katin got a phone call with the news that he had known all along: He was clean.
"It was extremely frustrating," Katin said. "I don't know why it took so long, but unfortunately it did."
Katin was allowed to play during his appeal.
"The worst part is I was playing every day with this hanging over my head," he said. "I think I was hitting .200 during that stretch."
Katin's positive test didn't send shock waves through baseball, as Braun's did. His Huntsville teammates knew, but that was it.
"I've been accused of [taking PEDs] my whole career because I'm a power hitting guy and weigh 230 pounds," Katin said. "People were like, 'Finally the truth comes out,' when it was me, and I'm like, 'C'mon guys.' When the final results were in, there was nothing. I had to deal with [accusations] for two months. It was extremely frustrating.
"It was definitely a difficult time in my life, just sitting there waiting, and there was nothing I could do," he said. "I was waiting for the final results."
He got the news when the Huntsville trainer handed Katin a piece of paper as he was boarding a bus for a game in Chattanooga.
"It said, 'Congratulations, you won your appeal,' and pretty much, that was it," Katin said.
He never got an explanation for the high levels of testosterone, but said it may have been caused by having a few drinks the night before the test.
Katin and Braun were teammates at Miami -- Braun played third then -- and also in the Brewers' system. Last year, Katin batted .239 with 11 homers in 34 games for Milwaukee's Triple-A team in Nashville. Braun had an MVP season with the Brewers, leading them to the National League Central title. He's appealed his 50-game suspension.
Katin's future is uncertain. He's scheduled for surgery in January on his right knee to repair the meniscus, and hoping to come back and try again in 2013.
He hasn't reached out to Braun.
"Not at all," Katin said. "I'd just let it take its course. It's obviously on a much higher scale. When I was appealing, nobody even knew about it. [Braun's case] has been out in public. Everybody knows about it."
He does empathize with Braun. Katin's been there.
"I feel like when it's all said and done, he'll be in the clear," Katin said of Braun. "I really believe that.
"I think anybody who knows him knows he's telling the truth," Katin said.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter@CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.