Andre Agassi has a stunning admission in his upcoming autobiography. Agassi says that when his career went into a tailspin in 1997 he started to using the drug crystal meth.

ESPN writes:

He'd sunk to No. 141 in the world. He recalls that he was sitting at home when his assistant, Slim, introduced him to one of the most addictive substances known to man:

Slim says, You want to get high with me?

On what?

Gack.

What the hell's gack?

Crystal meth.

Why do they call it gack?

Because that's the sound you make when you're high. Make you feel like Superman, dude.

As if they're coming out of someone else's mouth, I hear these words: You know what? F*** it. Yeah. Let's get high.

The book "Open: An Autobiography" comes out on November 9th.