He told the crowd: "I'm sorry I've never had to do this before but we've gotta stop. I can't sing. I don't know what else to tell you. I'm sorry. It's frustrating for me, I'm sorry. I promise that we will come back. This is our musical home, I'm sorry."
A spokesperson said that Flowers was suffering from a sore throat. The band also canceled last night's show at the same venue, but plans to reschedule.
A Facebook post from the guys said: "Manchester, we started something we couldn't finish and we're so, so sorry. Working on rescheduling shows. Will let you know new dates ASAP."
The band's shows at London's O2 Arena on tomorrow and Saturday will go on as planned.
Gotta' give him props for being honest!
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