Although they played BFFs on screen, Beverly Hills, 90210 stars Jennie Garth and Shannen Doherty were often at each other’s throats when the cameras weren’t rolling on the set of the 1990s teen drama.

Jennie makes the revelation in her juicy new memoir, Deep Thoughts From a Hollywood Blonde, revealing that she and Shannen were like “gasoline and a match,”; describing their relationship as “bitter rivals”; who fought constantly — while costar Tori Spelling tried to play peacemaker.

“I don’t know why it is, but there is a universal truth that when you put three teenage girls together, some serious s**t is going to go down,”; writes Garth in the just-released book. “Poor Tori, the youngest of the three of us was, inevitably, often caught in the middle and she was always trying to smooth things over, trying to get Shan and me off each other’s backs and get along, but her efforts usually failed.”;

BATTLE OF THE “90210′ MEMOIRS

Jennie also dispels one of the “great 90210 legends”; that she and Shannen actually “came to blows one time,”; admitting that while it never actually happened, “we did come very, very close.”;

“We were shooting a scene and Shannen kept grabbing at the hem of my skirt, trying to slap me on the leg — anything to get me to react and break character,”; explains Jennie. “Finally, when she’d pulled up my skirt, and my bare ass was exposed for everyone on the set to see, I did snap and I yelled at her, something to the effect of, “Come on, b***h! We’re talking this outside!'”;

Fortunately for everyone, Luke Perry and Jason Priestley stepped in and separated the women “before we could kill each other.”;

Ultimately, Jennie writes, she and Shannen made peace with each other. “Now I count her as one of my dearest, closest friends.”;

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