Justin Timberlake is set to launch his first U.S. tour in five years later this month, but sources say he’s worried sick about the backlash from ex Britney Spears’ loyal fans!

The 43-year-old “Cry Me a River” singer’s reputation took a hit after Britney roasted him in her recent memoir, The Woman in Me. She opened up about their relationship, branding Justin a serial cheater, and revealed that he convinced her to get an abortion after they unexpectedly became pregnant. 

“Justin’s already faced a big backlash on social media and a blow to the nice guy reputation he’s always tried to nurture,” the source exclusively tells In Touch. “Now he’s going to put himself out there for public scrutiny, and he’s really worried this tour could turn into a disaster!”

Timberlake will try to get ahead of any potential fireworks by addressing the Britney situation at some of the early dates on the tour, which begins April 29, “in hopes it will all just go away.”

But the former N’Sync boybander has already taken a hit from the Britney Army. Shortly after releasing his new single, Selfish, her fans pushed a 13-year-old Britney song with the same title up the charts to compete with him.

Although Britney, 42, recently apologized for damning Justin and even complimented him on his new music, he still fears the impact of her rabid fans.

“Britney’s revelations boxed Justin into a corner,” says the insider. “He’s really afraid he’s going to be hounded by her fans on this tour.”

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