Brian Austin Green Remembers Being 'Incredibly Jealous' During Tiffani Thiessen Romance

Jealousy got the best of Brian Austin Green on the set of Beverly Hills, 90210.

The 50-year-old actor admitted on the latest episode of former costar Shannen Doherty's Let's Be Clear podcast that he now regrets how he handled his then-girlfriend Tiffani Theissen joining the cast of the teen drama series in its fifth season.

"I'd never been in a real serious relationship before," he shared. "I was incredibly jealous every time she would f---ing have to work with anybody else because we'd already been doing the show for four years. Like, this is my family."

The Dancing with the Stars alum — who dated Theissen for three years from 1992 to 1995 — revealed that he struggled with seeing the actress get close with his costars.

"I used to bring Tiffani to events so she knew everybody from then and then all of a sudden she's doing sex scenes and s--- with people that were like my family and my brothers," he explained. "It was strange. I remember I was really just f---ing jealous and boisterous."

Green — who is now engaged to Sharna Burgess — shared that he handled the situation poorly and allowed his emotions to get the best of him.

"Looking back on it, I can't imagine what that was like for her," he admitted. "I can't imagine what it was like for her being with me for three years at that point and then having to do these scenes and having her f---ing boyfriend, who she lives with by the way, freaking out the way that I was."

In 2015, Thiessen, 50, opened up on The Meredith Vieira Show about her first on-screen kiss with their late costar Luke Perry.

"That was probably the more awkward thing,” she recalled. “Literally having your boyfriend on the show and then literally kissing another man, 'I get paid for this, honey. I don't know what to tell you.'"

Despite the on-set antics, Thiessen shared there was no bad blood between her and Green, saying, “We made it work. We are still very close and good friends.”

Green also gave a special shout-out to the important women in his life — including Thiessen — on International Women's Day in 2021.

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The actor shared a series of photos on his Instagram Story featuring him with his now-fiancée Burgess, as well as exes Theissen, Vanessa Marcil and Megan Fox. He also shared another photo of his mother, Joyce, holding him as a baby.

"Happy International Woman's Day!!" he wrote on each photo.