Shia LaBeouf spent months "living in the park" while preparing for a Broadway role

He told The Hollywood Reporter: "When [Alec] came in, I'm living in the park and I'm on steroids and I'm not in a good way...

"I was sleeping in Central Park. They keep horses there at this little fire basin. And there's a whole lot of room around there where you can just chill. You got to move every three or four hours and the guy comes around, but you can spend most of your time there."

He then clarified: "For most of the prep."

Shia - who eventually left the production due to the tensions - had originally been due to star in 'Orphans' with Al Pacino, but the 'Godfather' star dropped out close to opening night, leaving him feeling "insecure" and "desperate" to impress his new co-star, but Alec got "competitive" and things became "contentious".

He said: "By the time Baldwin got there, it was almost unfair. So he's dealing with both my fractured little weak ego, right? All this hard prep that I'd done for two years, and my desperate need to show him all my prep, or that he would accept me somehow. I was so insecure. Well, that got contentious in the room. Then he got competitive. That's just what our relationship turned into.

"I'd be off book, he'd be on book, and he didn't want me to look at him be off book. That makes it hard to play these scenes out or block this thing even. And no fault against him, he had two weeks to come in because Pacino [dropped out].

"I had built the whole thing based on my relationship with Pacino. And that's gone. So I was kind of heartbroken...

" And then Alec started teaching at NYU - a class on acting while I was doing these rehearsals with him. And I was like, "How? You're still not off book!" So then I started taking his class. It got insane."

However, the 'Honey Boy' actor noted he and Alec have "made it right" and are on good terms these days.

He added: "But me and him are good because he's gone through a lot. I've gone through a lot. We've both been able to send each other love and make it right before all the madness happened on both sides.

"We made it right. He's a good guy. He's just like me. Fear will make you move different. I found it came from having absolutely no spiritual life.

"It made me a piece of s***. Not a nice guy."

Alec previously admitted he had offered to step away from the production due to the "friction" between him and Shia, but his co-star was let go instead.

He told Vulture in 2014: "There was friction between us from the beginning. One day he attacked me in front of everyone. He said, 'You're slowing me down, and you don't know your lines. And if you don't say your lines, I'm just going to keep saying my lines.' I asked the company to break.

"And I took the stage manager, with [director Daniel] Sullivan, to another room, and I said one of us is going to go. I said, 'I'll tell you what, I'll go.' I said, 'Don't fire the kid, I'll quit.' They said no, no, no, no, and they fired him. And I think he was shocked."