BASHED BON JOVI NEEDS A TUNE-UP!

Livin' on a prayer unless he begs Sambora back

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Jon has had a string of shaky vocal performances

Guitarist Richie left the band in 2013 to focus on his family

STUBBORN Jon Bon Jovi is being told to swallow his pride and beg former pal Richie Sambora to rejoin his namesake band to save its wretched reputation, industry insiders dish.

"Bon Jovi needs something right now because Jon is in such bad shape," spills a source.

As The National ENQUIRER reported, the band recently performed a stretch of shocking concerts, where frontman Jon, 60, failed to hit his high notes. Critics savaged the "Bad Medicine" singer for his shaky vocals, and some fuming fans even stormed out of the shows!