NEW YORK—Former St. Louis Cardinals slugger, onetime single-season home run record holder, and admitted steroid abuser Mark McGwire came clean Monday, confessing that it was really fucking fun being able to hit baseballs so hard and far.

"I can't remember having a better time in all of my life," McGwire said during an hour-long interview with the MLB Network's Bob Costas. "Do you have any idea what it's like knowing instantly that a ball you hit is going to fly—no, soar—over a fence in a major-league stadium? Well, I do. And it's fucking fantastic."

"I'm sorry everyone had a problem with it," McGwire added. "But I was having a blast."

Though McGwire told Costas there were times he almost regretted taking anabolic steroids, the former Oakland Athletics star said that, considering the tons of fun the performance-enhancing substances allowed him to have, he never thought twice about his decision.

"I was hitting baseballs over 450 feet," McGwire said. "That's really far. And high, too. Oh my God, were they high. Towering, in fact. I was, like, crushing these things."

According to McGwire, he had the most fun during the 1998 season, when he fired off 70 home runs and broke Roger Maris' single-season long-ball record. McGwire said he had the second-most fun the following year, when he hit 65 home runs, many of which, the giddy slugger proclaimed, "went for miles and miles."

However, a visibly emotional McGwire admitted that he had absolutely no fun in 1993 and 1994, when he was plagued by injuries and hit just nine home runs each season. At that time, the first baseman explained, the balls were either going high and not that far or traveling too low and not that hard.

"That was a drag. Don't get me wrong, just hitting the ball really high in the air can be cool sometimes, even if you get out," said McGwire, adding that it's enjoyable to watch a routine pop-fly that goes "way, way up there." "But I was getting out a lot during those years, so I had to do whatever was necessary to hit the ball really high, far, and hard all the time."

"High plus far plus hard equals big-time, serious fun," McGwire continued.

McGwire also said that his decade-long steroid abuse had little to do with gaining an edge on his competition and more to do with his observation of how players who didn't hit the ball very far were not enjoying the game.

"I would look at a guy like John Olerud just kind of hitting these dinky ground balls, and I would say to myself, 'No way this guy's having a good time,'" McGwire said. "All I know is, when I got up to the plate, the outfielders would back all the way up because I hit the ball so far. I really enjoyed that."

"I also liked hitting it over their heads," McGwire added while flexing his right bicep and then making a swinging motion with his arms. "Crack! Home run."

According to the three-time Silver Slugger Award winner, the fun he was having also seemed to make everyone else—including teammates, fans, and Major League Baseball commissioner Bud Selig—have fun while they watched his at bats.

McGwire said that the main thing he learned in his 16 years as a player was that people tend to be happier when players are hitting the ball really far.

"By their reactions, I just figured they were cool with me taking steroids and having a good time," McGwire said. "They clearly knew I was taking performance-enhancing drugs, right? I mean, look at me. I look like a fucking monster. Plus, come on—I was hitting the ball really, really fucking far."