It’s a dark day for Three Days Grace fans. The group has announced on their website that lead singer Adam Gontier has quit the band, citing “a health issue” as the cause of his departure.  In addition, the band reveals that My Darkest Days frontman Matt Walst has stepped up to fill in for Gontier on their upcoming co-headlining tour with Shinedown .

"We were surprised and distressed by Adam's sudden departure,” said bassist Brad Walst in a statement.  “We are however very excited for this upcoming tour, and to have my brother Matt stepping in as lead singer."

To give fans an idea of what Matt will sound like as the lead singer of Three Days Grace, the group has posted on the band website new versions of Matt singing "The High Road," "Chalk Outline" and "Riot."

Three Days Grace kicks off their tour with Shinedown on February 1 at the iWireless Center in Moline, IL.   P.O.D. will support the bands on all dates.

Visit ThreeDaysGrace.com to view the full itinerary.

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