McGwire, who hit 583 career home runs, admitted his use of performance-enhancing drugs in 2010.
Although he was one of the best power hitters of his generation, Mark McGwire's legacy took a significant hit in 2010, when he admitted to using performance-enhancing drugs throughout his career, including during his record setting 70 home run season in 1998.
However, McGwire, who is now a bench coach for the San Diego Padres, told Jayson Stark on his new Stadium TV series Baseball Stories he still would have hit 70 homers without PEDs.
"I just know myself. I just know," he told Stark. "I was a born home-run hitter. I mean, unfortunately, I did (take PEDs). And I've regretted that. I've talked about that. I regretted it. I didn't need to. That's the thing. Didn't need to."
When Stark asked McGwire whether he could replicate his historic 1998 season without PEDs, he replied:
"But I know. Deep down inside, I know me as a hitter. And I know what I did in that box. And I know how strong my mind is. And I know what kind of hitter I became. And yes. Yes. Definitely."
McGwire and Sammy Sosa are widely credited with helping reinvigorate American interest in baseball, as their home run race in 1998 engrossed the nation. Big Mac slugged his 62 home run of the year on Sept. 8, passing Roger Maris for the most home runs ever in a single season. He finished with 70 homers on the year, with Sosa hitting 66 long balls to keep pace. McGwire's record would later be broken by slugger Barry Bonds, who holds the single season record with 73 in 2001.
Although McGwire is confident he could have hit 70 long balls without PEDs, Victor Conte, the man at the heart of MLB's BALCO steroid scandal for developing PED programs for athletes, told Josh Peter of USA Today Sports he doesn't think McGwire could have broken the home run record without assistance.
"I think Mark McGwire is deluded if he thinks he would have hit 70 home runs without using PEDs in 1998," Conte told USA Today Sports.
The 53-year-old McGwire said he had deep regrets about his use of PEDs and told Stark he supported MLB's current enforcement efforts.
Although he admitted to using PEDs, McGwire, who hit 583 career home runs for the St. Louis Cardinals and Oakland Athletics, is unlikely to garner enough votes on Hall of Fame ballots, as he has never received more than 23.7 percent of the vote in 10 eligible years.