Brad Pitt is said to have become “volatile when riled” on the set of his ‘Legends of the Fall’ film.

The 60-year-old ‘Fight Club’ actor starred in the Western in 1994 and its director Ed Zwick, 71, has now opened up about what it was like to direct the star – revealing one of their bust-ups ended with a chair being flung.

He says in his ‘Hits, Flops, and Other Illusions: My Fortysomething Years in Hollywood’ memoir: “It fell to (producer) Marshall (Herskovitz) to talk Brad off the ledge.

“It was the first augury of the deeper springs of emotion roiling inside Brad. He seems easy going at first, but he can be volatile when riled, as I was to be reminded more than once as shooting began and we took each other’s measure.”

Ed, whose other films include ‘Blood Diamond’ and ‘The Last Samurai’, added Brad and his relationship would grow strained as the A-lister would allegedly “get edgy” when “he was about to shoot a scene that required him to display deep emotion”.

The director added he would try and push the actor out of his comfort zone because he had grown up with men in the Ozarks “who held their emotions in check” and he wanted the character to show true emotions.

But Ed admitted about the strategy backfiring: “Yet the more I pushed Brad to reveal himself, the more he resisted.

“So, I kept pushing and Brad pushed back.”

Ed said one particularly heated face-off ended with a chair being thrown when he gave Brad a direction in front of the crew, which he admitted was a “stupid, shaming provocation”.

He said: “Brad came back at me, also out loud, telling me to back off… I was angry at Brad for not trusting me to influence his performance.

“Also for the reluctance he’d shown after the first table read… but Brad wasn’t about to give in without a fight.”

“In his defence, I was pushing him to do something he felt was either wrong for the character, or more ’emo’ than he wanted to appear onscreen.

“I don’t know who yelled first, who swore, or who threw the first chair. Me, maybe? But when we looked up, the crew had disappeared.”

Ed stressed that even though he and Brad would have regular “blow ups” they would always “make up and mean it”.