"I think Richie's doing all right, [but] I haven't spoken to him," Bon Jovi told the Austin (Texas) American-Statesman.
"We were surprised. It was 3:30 on show day on Tuesday and we got a phone call that he wouldn't be there. It's a personal matter."
Canadian guitarist Phil X has replaced Sambora for the rest of the tour, the American-Statesman said.
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