Canseco says yes.
McGwire says no.
In Canseco's mind, there's only one way to break the deadlock.
A live televised polygraph test!
"I've got no problems with a few of the things he's saying, but again, it's ironic and strange that Mark McGwire denies that I injected him with steroids," Canseco said. "He's calling me a liar again. I've defended Mark, I've said a lot of good things about him, but I can't believe he just called me a liar.
"There is something very strange going on here, and I'm wondering what it is. I even polygraphed that subject matter - that I injected him - and passed it completely. So I want to challenge him on national TV to a polygraph examination. I want to see him call me a liar under a polygraph examination."
The story of Canseco and McGwire injecting each other before games in the late 1980s was just one of many steroid accusations Canseco made against other baseball players in his 2005 book "Juiced," which ultimately proved to be a turning point for steroids and baseball.
McGwire, however, said on MLB Network on Monday night that Canseco made up that passage. "There's absolutely no truth to that whatsoever . . . I couldn't be more adamant about that," he said. Asked why Canseco would then include that, McGwire said, "He had to sell a book."