Young Stud Bursts B&B hunk’s bubble!

Thorsten kate pierson fode bold and the beautiful sq

Soap hunk Thorsten Kaye is being challenged for his place in "The Bold and the Beautiful" top-tier cast by his own TV son!

As ratings slide, B&B execs are trying to grab younger viewers — and older stars like Kaye are getting shunted aside. So devilishly handsome 24-year-old Pierson Fodé, who plays Kaye's son Thomas Forrester, is now the flavor of the moment.

Fodé, who joined the cast earlier this year, will “make his bones" at Kaye's expense. “It’s like they’re pitting Thorsten and Pierson against each other now,” the source says.

Thorsten, 50, became a fan fave after taking the role of Ridge Forrester in 2013. “But now he's fighting for his acting life — and he knows it,” says the source.