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Bon Jovi guitarist Richie Sambora is expressing his appreciation to the fans.  But he's remaining vague on just why he's left the band in the middle of their tour.  The rocker shared via Twitter:

Meanwhile, Bon Jovi has tapped guitarist Phil "Phil X" Xenidis to fill in for Sambora.  The band posted a photo late Wednesday of their interim guitarist and frontman Jon Bon Jovi, with the message, "We welcome Phil X back to the tour."  Phil previously performed with Bon Jovi in 2011, when Sambora skipped a number of tour dates to enter rehab. 

Bon Jovi played their first concert without Sambora Tuesday night in Calgary.  On Wednesday the band posted a message on their website that reads, "Due to personal issues, Richie Sambora will not be performing on this upcoming leg.  All shows will go on as scheduled."  Bon Jovi has also offered refunds to any ticketholder who wants one. 

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